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Seahorse Attacked - Please Help!

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Seahorse Attacked - Please Help!

I have been having problems with long hair algea in my seahorse tank. I was told that I could get a Lawnmower Blenny to help with the algea and it would co-exist with my Seahorses. It did fine for about a week, then the Blenny started going after my Seahorses. I was able to catch and remove the Blenny but my Seahorses stayed near the top of the water for about 24 hours, with fast breathing and not eating. I was hoping it was just because they didn't realize I took the Blenny out. It's now been 1.5 days and my smaller Seahorse has slowly started moving around, looking for food but still breathing fast and not really eating anything. My larger Seahorse has not moved from the top of the tank (that I have seen), is showing no interest in food, and is breathing fast. They both are developing this white stuff on the sides of them, the larger Seahorse almost looks like he has a swollen circular area on his side. I'm almost certain that it was caused by the stress of the Blenny since they both are acting the same way, showing the same symptoms and it all started at the same time as the Blenny going after them. Any help on what I should do to help then would be greatly appreciated.

Thank you,

Pete Giwojna
Dear Lora:

Dear Lora:

I'm sorry to hear about the problem that the lawnmower blenny cost for your seahorses.

Unfortunately, they cannot be trusted with seahorses as you've discovered a little too late.

This is what I usually advise home hobbyist regarding the lawnmowers, Lora:

Lawnmower Blennies

For starters, I can tell you that you must not take a chance on keeping a lawnmower blenny with your seahorses. That's an experiment that has been tried many times, and it often results in the death of the seahorses. There are some types of blennies that do quite well with seahorses, such as the Midas blenny and often the scooter blenny, but, unfortunately, the lawnmower blenny (Salarias fasciatus) is not one of the compatible blennies. They can be problematic with seahorses and must always be regarded with caution.

For example, Kevin Frenzel and Renée Hix categorize lawnmower blennies as a "3" on their scale in their seahorse compatibility guide. A reading of 3 indicates the following:

"3 - I wouldn't keep any of these critters with my seahorses, but you're welcome to try. 3's are on the dangerous side. The fish will not only be in the water column but often have a distinct presence. There is a good chance for food competition and aggression."

I would agree with that assessment, Lora, and I typically advise seahorse keepers to avoid lawnmower blennies. Just a few weeks ago, I received a report from another hobbyist (Katie) who had lost two of her Ocean Rider seahorses to attacks from a rogue lawnmower blenny. Katie's seahorse tank is a 92-gallon aquarium with lots of live rock and she had a dreadful time capturing the aggressive blenny because there are so many hiding places in the rockwork. She eventually had to systematically remove the live rock temporarily so that she could remove the blenny before more damage was done to her other ponies.

I recently also received a report from David and Sheena Mikesell, who had just introduced four Ocean Rider seahorses into their home aquarium, and lost two of them for no apparent reason in the next few days. The only discovered the reason for the deaths later that weekend when they witnessed their lawnmower blenny viciously assaulting another of the ponies. This time they were able to intervene, but the seahorse unfortunately died several days later from its injuries. In less than a week, their lawnmower blenny managed to kill three of their four new seahorses without being detected doing its dirty work until both Dave and Sheena were home on the weekend and observing the remaining seahorses closely for any sign of a problem…

And I had another hobbyist (Deborah) who contacted me asking about the behavior of her lawnmower blenny, which wasn't viciously attacking her seahorses, as happened with Katie and the Mikesells, but rather was "mouthing" them the same way it did when cleaning algae off of the rockwork or decorations. In other words, Deborah's lawnmower blenny would periodically clean one of her seahorses as if it were part of the aquarium decor.

As you can imagine, her seahorses were always somewhat traumatized when the lawnmower blenny would do his cleaning, and would be very apprehensive and reluctant to feed afterwards. Of course, the unwanted attention of the lawnmower blenny was also compromise the seahorses' protective slime coat, which left them susceptible to disease problems, and the seahorses were very intimidated by the blenny, and she also had to remove her lawnmower blenny, even though it didn't seem to intend any harm to the seahorses directly.

Those are only a few most recent examples of the type of reports I hear regarding lawnmower blennies all of the time, Lora.

Whatever you have any questions or concerns about the compatibility of specimens that were not specifically mentioned in Lesson 6 of the seahorse training program, which is devoted to suitable tank mates for seahorses, just go online and check out the following webpage:

Tankmate Guide for Seahorses by Kevin Frenzel and Renée Hix


The only thing I can recommend that might aid your seahorses to get back to normal and bounce back following their experience with your lawnmower blenny, would be to treat them with a good antibiotic to prevent any secondary infections from stress or any injuries that the blenny may have caused. The antibiotics that work best for most home hobbyists when treating seahorses are Furan2, which can be used all by itself, or a group of medications by SeaChem that can be used together and mixed with frozen Mysis in order to administer the medications orally.

The SeaChem medications that work best for this purpose are SeaChem, KanaPlex, SeaChem NeoPlex, and Focus by SeaChem.

The active ingredient in SeaChem KanaPlex is kanamycin sulfate, a potent aminoglycoside antibiotic that is a very broad spectrum, and which can be combined with the neomycin sulfate (another aminoglycoside antibiotic) in SeaChem NeoPlex to create a synergistic effect that is more effective than either of these antibiotics used by themselves.

The SeaChem NeoPlex contains neomycin sulfate, a good aminoglycoside antibiotic that is very effective when ingested, and the SeaChem Focus contains a good nitrofuran antibiotics and is the perfect medium for mixing medications with frozen foods. I will explain more about how to use these two products together for you below.

Both the NeoPlex and the Focus come with little scoops for measuring out the proper dose of the medication, Lora, and preparing the frozen Mysis with the medications is actually pretty easy. First, you want to find out how much of the Mysis you are using amounts to a tablespoon. I imagine that several of the cubes of Mysis would be needed to fill a tablespoon after you have thawed it out as usual, if that's the form of frozen Mysis you happen to have. (It's important to find out how much of the thawed Mysis constitutes 1 tablespoon because the correct dosage for NeoPlex is one scoop or measure per tablespoon of Mysis.)

Once you have thawed out 1 tablespoon of the frozen Mysis, you then measure out one scoop of the NeoPlex and five scoops of the Focus and mix the two medications thoroughly so that they bind together. (You always add five times as much of the Focus as the amount of antibiotic you are using.) Once you have mixed the powdered NeoPlex and Focus together very well, you then add the resulting mixture to the tablespoon of thawed Mysis you have prepared and very gently but thoroughly mix the powder and Mysis together so that the medications bind to the shrimp. You can then either feed the medicated Mysis to your seahorses immediately or freeze it for later use.

Once you have prepared the medicated Mysis, you feed it to your seahorses twice a day for at least five consecutive days or as long as is takes for the symptoms to clear up.

Of course, you can prepare more than 1 tablespoon of the medicated Mysis at a time in order to make it more convenient, Teresa. For example, if you wanted to prepare 5 tablespoons of medicated Mysis's at one time, you would thaw out 5 tablespoons worth of your Mysis in advance. Then you would take 5 scoops of NeoPlex (one scoop of NeoPlex per tablespoon) and 25 scoops of the Focus (5 times as many scoops of Focus as the antibiotic) and mix it together thoroughly with the five scoops of NeoPlex so that they blend together and bind. Finally, you would take the mixture of powders and gently but thoroughly combine the powdered medications with the thawed Mysis so that the medicine also binds with the shrimp.

If you want to prepare extra medicated Mysis in advance, it's best to spread it out on a piece of Saran wrap or Glad wrap or aluminum foil, or something similar, so that you can cover it completely to protect it from freezer burn until you're ready to use it.

Here is some additional information on the Focus by Seachem Laboratories, which explains how to use it to combine medication with food:

Seachem Laboratories Focus - 5 Grams Information

Focus ™ is an antibacterial polymer for internal infections of fish. It may be used alone or mixed with other medications to make them palatable to fish and greatly reduce the loss of medications to the water through diffusion. It can deliver any medication internally by binding the medication to its polymer structure. The advantage is that the fish can be medicated without contaminating the entire aquarium with medication. Fish find Focus™ appetizing and it may be fed to fish directly or mixed with frozen foods. Focus™ contains nitrofurantoin for internal bacterial infections. Marine and freshwater use. 5 gram container.

Types of Infections Treated:


DIRECTIONS: Use alone or in combination with medication of your choice in a 5:1 ratio by volume. Feed directly or blend with fresh or frozen food. Feed as usual, but no more than fish will consume. Use at every feeding for at least five days or until symptoms clear up.

Contains polymer bound nitrofurantoin.

Active ingredient: polymer bound nitrofurantoin (0.1%). This product is not a feed and should not be fed directly. Its intended application is to assist in binding medications to fish food.

And here is an excerpt from an e-mail from another home hobbyist (Ann Marie Spinella) that explains how she uses the NeoPlex together with the Focus for treating her seahorses, Lora:

"When I bought the NeoPlex yesterday I also picked up a tube of Focus. According to the instructions, it says it makes the medication more palatable to fish and reduces the loss of the medication once it's in the water.

So I followed the dosing instructions exactly. I used regular frozen Mysis instead of Piscine Energetics frozen Mysis. I figured it was softer and smaller. I was thinking along the lines of more surface area for the medication to adhere to, and with the softer shell, hopefully it would absorb into the shrimp a little better.

I used 8 cubes which came to just about 1 tablespoon. I thawed and rinsed the shrimp thoroughly in a little colander and let it sit on a paper towel to remove as much water as possible.

Then I put in it in a small dish and added the Focus and NeoPlex in the recommended ratio which is 5:1 (5 scoops Focus / 1 scoop NeoPlex). I mixed it thoroughly and added a few drops of Garlic Power.

Then I measured out 5 - 1/4 tsp. servings and 4 servings I placed on a sheet of Glad Press & Seal, sealed them and put them in the freezer, since it says in the instructions that you can freeze what you don't use right away, and the remaining 1/4 tsp. I split in half and fed to them this morning. The rest I'll give to them this afternoon and I'll do this every day with the remaining shrimp that I already prepared and froze.

In the video you can see that the seahorses are eating it. Yea!!

Thanks for all of your help & I'll keep you posted."
Ann Marie

Okay, Lora, that's the rundown on using the NeoPlex together with the Focus so that you could administer the medication in the NeoPlex orally after adding it to the frozen Mysis for the seahorses daily meals. If you got the KanaPlex instead of the NeoPlex, it can be combined with Focus and administered in exactly the same way as outlined in the instructions for the NeoPlex above.

You can feed the medicated Mysis to your seahorses twice a day until they are back to normal again and all is well.

If you obtain the Furan2 instead of the SeaChem medications, Lora, then I would recommend administering it as follows:

For best results, I would suggest gutloading live adult brine shrimp with the antibiotic and then feeding the medicated adult brine shrimp to the seahorses twice a day for the next 10 days. This will allow you to treat the ponies in your main tank, where they are most comfortable, which is the least stressful way to administer the medication. I would suggest using Furan2 for the antibiotic, since it is readily available at most local fish stores and is most effective when it is administered orally, as explained below:

FURAN-BASED MEDS (oral) Dosage and Preparation Instructions
Active Ingredients: Nitrofurazone and/or Furazolidone
Indication: bacterial infection
Brand Names: Furan-2, Furanase, Binox, BiFuran+, FuraMS, Furazolidone Powder
Feed adult brine shrimp gut-loaded with medication to the Seahorse 2x per day for 10 days.
• Add a small amount of the medication to one gallon of water and mix thoroughly.
• Place the amount of adult brine shrimp needed for one feeding into the mixture. Leave them in the mixture for at least 2hrs.
• Remove the adult brine shrimp from the mixture and add them to the hospital tank.
• Observe the Seahorse to be certain it is eating the adult brine shrimp.

Hopefully, your seahorses will recover from the aftereffects of your aggressive blenny and be back to normal again before you know it, Lora.

Please let me know if you are still having a problem with the hair algae and I would be happy to provide you with some tips for controlling and eliminating nuisance algae.

Pete Giwojna, Ocean Rider Tech Support

Dear Pete,

Dear Pete,

Thank you so much for getting back with me and for all of the helpful info on things to try! I have ordered the items you spoke of and will be administering them tomorrow. I hate that I put the Blenny in there as it is the thing that is causing them suffering, having all the info you sent over will definitely be a big help.

I am still having issues with the long haired algae along with maroon carpet like algae. I put Chemi-pure Blue in my canister filter about a month ago, hoping that it would help, but I don't believe I have seen a difference. I have had my water tested multiple times and they always say that 'it's perfect, especially for a tank that has been up for about a year'. I' love to hear any tips you can provide in trying to help me get rid of them both.

Thank you,


Pete Giwojna
Eliminating Green Hair Algae…

Eliminating Green Hair Algae…

In my experience, the best way to get rid of the green hair algae (Derbesia) once and for all is to maintain optimum water quality at all times, Lora, which it sounds like you have been doing very well, at least for the water quality parameters that you monitor.

But to rid your tank of green hair algae, it's very important to keep the phosphates at zero and the nitrates as close to zero as possible, and maintain the proper levels of pH, carbonate hardness/alkalinity, and calcium. If you can do that, the hair algae typically cannot thrive and will eventually disappear as suddenly as it appeared, but having a good cleanup crew with members that include hair algae on their menu will also be very helpful in that regard.

In most cases, you can eliminate the hair algae from your aquarium with a three-step process. The first step is to get the phosphate and nitrate levels in the aquarium down to zero. The second step is to make sure that the pH, carbonate hardness/total alkalinity, and the calcium and magnesium levels are in the proper range. And the third step is to physically remove as much of the hair algae as possible as often as possible and to make sure that your cleanup crew includes plenty of scavengers that like to eat the hair algae.

Let's discuss how to accomplish the three steps above in a little more detail below, Lora.

Very often, high levels of nitrate or phosphate are present in aquariums with excessive hair algae growth, and seahorses will begin to experience distress when the nitrates rise above 20 ppm.

Getting the nitrates and phosphates in your aquarium down to zero will help immensely in getting rid of the hair algae, Lora, but in stubborn cases that may not be enough.

In that case, Lora, you should also concentrate on adjusting the pH, carbonate hardness, magnesium, and calcium levels in the aquarium. If you can maintain the total alkalinity/carbonate hardness and magnesium and calcium at the high levels recommended for reef tanks and keep your pH in the proper range, the hair algae will often disappear on its own.

You may need some additional test kits and supplements to add to the aquarium to achieve the desired levels of phosphate, magnesium, calcium, and carbonate hardness, Lora, but that should certainly take care of your hair algae problem in an instance where it is growing despite a lack of nitrate or phosphate to fuel its growth. Here is some more information explaining the proper range to maintain your water chemistry in these areas:

Natural Seawater Value = 2.5 meq/L
Acceptable Range = 2.5 to 5.0 meq/L
Optimum Level = 2.5 milliequivalents per litre (meq/L)is best for fish tanks; > 3.0 meq/L but < 5.0 meq/L is recommend for reef tanks.

The alkalinity is basically a measure of the capability of your aquarium water to resist changes in pH from the addition of acid (Trevor-Jones, Nov. 2002). Acid is continually entering the aquarium, primarily as the result of respiration (CO2) and metabolic wastes produced by the aquarium inhabitants (Trevor-Jones, Nov. 2002). The addition of these acids tends to lower the pH of the aquarium water. The higher the alkalinity of your aquarium water, the more resistant it is to such downward pH shifts (Trevor-Jones, Nov. 2002). The amount of buffers (primarily carbonate and bicarbonate) in saltwater determines the alkalinity, so the alkalinity in effect is the buffering capacity (Trevor-Jones, Nov. 2002). When the buffering capacity of the water is depleted, the pH becomes unstable. A fluctuating alkalinity will lead to serious problems in maintaining an appropriate pH, as well as problems keeping calcium and magnesium levels within required ranges. Alkalinity test kits can now warn of low buffering levels in time to prevent potential pH problems (Trevor-Jones, Nov. 2002).

Carbonate Hardness (KH):
Natural Seawater Value = 7 dKH
Optimum Level = 7dKH (for seahorses)

Carbonate hardness is another measurement of alkalinity. It is usually expressed in the German unit dKH (degrees of carbonate hardness) and is often considered to be the total alkalinity. (Dividing dKH by 2.8 will give you the alkalinity in meq/L.) KH is actually a measurement of various carbonates and bicarbonates of calcium and magnesium within the aquarium water (Webber, 2004). Maintaining a stable KH is very desirable since it maintains the buffering capacity (i.e., alkalinity) of the system and prevents subsequent drops in pH. Aside from stabilizing the pH, reef keepers need to maintain KH and high alkalinity in order to assure that the calcifying organisms in the tank flourish. For this reason, although 7dKH is excellent for a seahorse only setup, or a tank with seahorses and a few hand-picked soft corals, aquariums with stony corals, calcareous macroalgae, or a lot of coralline algae can benefit from a somewhat higher KH reading. A good brand of artificial sea salt for a reef tank will yield a KH between 8-12 after being freshly mixed, in order to allow for the calcification that will occur once the water change is made. Corals and other calcifying organisms actively use bicarbonate, which is the main component of alkalinity, so the alkalinity of a tank with a lot of calcification can drop quite rapidly. However, you do not want the KH in the aquarium to rise above 13dKH for any length of time since KH readings in the 14-15 range and above can cause calcium to begin to precipitate out of the water, making it increasingly difficult to maintain an adequate calcium level in the aquarium...

Calcium (Ca):
Natural Seawater Value = 400 mg/L
Acceptable Range = 350 to 450 mg/L
Optimum Level = 350 - 400 mg/L (up to 500 mg/L in well-stocked reef tanks)

Calcium is a very important element in the water in any marine aquarium and is a vital element in reef tanks. Along with carbonates and bicarbonates, it is required by calcifying organisms such as stony corals, snails and other mollusks, coralline, Halimeda and other calcareous algae, and certain sponges (Trevor-Jones, Apr. 2003). Calcium is a critical parameter for coral growth in reef aquariums, and chronically low levels will cause coral mortality and loss of coralline algae and other invertebrate species. Calcium reserves must therefore be replenished on a regular basis. Regular water changes may achieve this, but reef keepers may require the addition of biologically available calcium to maintain adequate levels (Trevor-Jones, Apr. 2003). Seahorse keepers should be aware that brooding males provide calcium to the developing fry in their pouches, which the embryos probably incorporate into their skeletons. Deficiencies in calcium could thus adversely affect your seahorses’ reproductive success and the health of the fry. In fact, seahorses that receive a diet deficient in calcium often suffer from decalcification of their exoskeleton, a debilitating condition commonly known as “soft plate” disease (Greco, 2004).

Magnesium (Mg):
Natural Seawater Value = 1280 mg/L
Acceptable Range = 1100 to 1400 mg/L
Optimum Level = ~1280 mg/L

Magnesium is a key component of the water buffering system, and is incorporated into coral skeletons as the corals grow. It also plays a vital role in all photosynthetic processes. Low levels of magnesium indicate the need for more frequent partial water changes and/or buffering of the aquarium.

In short, Lora, I would get test kits for total alkalinity and/or carbonate hardness, plus calcium and magnesium test kits, and adjust those levels as indicated above.

The appearance of the hair algae suggests that you may have excess nitrates and phosphates in the tank, Lora, and the first thing you'll want to do in order to get this problem under control is to make sure your water quality is up to snuff, as we discussed previously. You'll want to make sure that you have as close to zero nitrates and zero phosphates as possible, and you'll want to make sure that the pH, total alkalinity, and calcium levels in the aquarium are at the right level.

Many times nitrates and phosphates enter the aquarium in tap water, so you'll want to switch to RO/DI water if you have been relying on tap water when mixing up saltwater for your seahorse tank, Lora.

If you can make sure your water quality is optimum, with as little nitrate and phosphate as possible, and the pH, alkalinity, and calcium levels within the normal range, then manually removing as much of the hair algae as possible on a daily basis and maintaining plenty of herbivores in your cleanup crew that include hair algae in their diet will eventually allow you to clear it from your tank.

But you have to be careful when removing hair algae from your tank, Lora, because it can spread by fragmentation. I recommend using the method described in the following article for manually removing the green hair algae:

Green Hair Algae: Why me?!


Green Hair Algae (abbreviated as GHA for this article) - Derbesia - is a form of algae that looks like its name. It is usually dark green, grows quite long if left unattended and spreads across your tank rapidly. Once this problem has begun, it can get out of hand in a matter of weeks. And soon you start to look at your tank in disgust, thinking “Why me? What did I do to deserve this plague?”

A number of things may have contributed to it getting a foothold in your system. Your nitrates might be too high, your phosphates may be too high (.03 or less is the goal), your lighting has recently been replaced or perhaps your bulbs are so old that the spectrum of light has shifted, fueling algae growth.

First things first. You need to get your water parameters to Natural Sea Water levels:
pH 8.0 - 8.3
Ammonia 0
Nitrites 0 hope
Nitrates 10ppm or less
Alkalinity 8 - 11dKH
Specific Gravity 1.026
Calcium 400 - 450
Phosphate .03 or less

A lot of these are affected by the water quality you use before you even begin to mix your saltwater. If you use tap water, you might be adding nitrates or phosphates to your tank on a daily or weekly basis. RO/DI water is your best and most pure option. If your phosphates are high, you can use products like Kent’s Phosphate Sponge (white granules) that fit in a filter area that will reduce them from 2.0 to .2 in 48 hours.

Okay, so your water is great. To get rid of the algae, you are going to have to prune it back manually. Fortunately, you can get some help from ocean dwellers, but like anything, when you have too much of something, you have to get radical to bring it within manageable levels. Nothing good ever happens quickly, right? This is going to take some specific attention on your part for a few weeks, but you can overcome it.

Get a container of fresh water (tap is fine) and put it near your tank. I like to have it on the top edge of the tank. If you can clip it to keep it in place, even better. Reach into your tank, and pinch off a clump of the stuff. Pull your hand out still pinching the GHA so none of it gets released into your tank, and dip/rinse your fingers off in the water. Repeat this a hundred times.

The reason you rinse your hand after each pinch is to prevent the filaments from floating around in your tank and reattaching elsewhere, just spreading your problem further!

When your hand gets tired, switch to the other hand. Take your container and dump it out, rinse it well and put more water in it and get back to work. Try to remove as much as you can see and reach, working at this daily. By ripping it out in bulk, you prevent it from spreading, and you give your hermit crabs and snails something they can actually keep up with. Buy more snails to help with the battle. I prefer Turbo snails.

Whenever you see a snail that is not working on the GHA, pull it off the glass/powerhead/plumbing and put it on an area of algae. They work for you.

Clean your skimmer completely. Clean the pump/powerhead thoroughly, make sure your air intake is clear. Clean your collection cup often, so you don’t have slime buildup hindering it. You want to skim out as much of the Dissolved Organic Compounds (DOCs) before they can break down in your tank and add to the A-N-N cycle. Remember nitrates fuel algae growth. You want 10ppm or less to avoid feeding GHA. If your skimmer is underpowered for your tank, seriously consider upgrading to a better unit.

If you’ll keep up with this process for a few weeks, you’ll see less and less in your tank, until one day, your tank is pristine again. If you come to visit, you’ll see my little reef is cured, but it did take time and effort.

Okay, Lora, those are some tips that should be very helpful in eradicating the nuisance algae from your aquarium, including the stubborn hair algae. Here are some more suggestions that you may find helpful in that regard.

The hobbyist should also be aware that dead spots and low flow areas, as well as low pH levels, favor the growth of nuisance algae rather than coralline or macroalgae and marine plants. Eliminating dead spots and stabilizing your pH at 8.2 - 8.4 can therefore help tip the balance back in the favor of macros and coralline algae, and help prevent problems with nuisance algae.

One simple measure that can thus make a big difference is to try positioning one or more small powerheads so that they increase the circulation in the area where the nuisance algae tends to grow. Better water movement and higher oxygen levels will naturally tend to minimize the growth of slime algae and hair algae in these problem areas. Just be sure to shield or screen off the intakes for the powerheads so that a curious seahorse won't get its tail injured by the impeller.

In summary, some of the measures that will help control nitrates and phosphates (and excess nutrients in general), or otherwise help control nuisance algae in the aquarium are the following:

1) Make sure your protein skimmer is working correctly. A protein skimmer works 24 hours a day to remove excess waste and nutrients from a tank. If the venturi is clogged on a venturi skimmer or there is another problem with other skimmer designs, waste will not be exported from your tank and algae will take advantage of the waste. In order to function efficiently, the protein skimmer must be cleaned regularly, including inside the cylinder where the bubble column forms to provide the foam fractionation.

2) Perform regular water changes. Regular water changes will decrease the level of wastes and nutrients in the water. But the water changes won't do much good if your tap water itself contains phosphates and amines. Depending on how high the nitrate levels become, increasing the proportion of water that you change each time may be necessary to help reduce those nitrates. There is an article about nitrate reduction at <<>> in the saltwater section that really explains water changes (gives you the math), on actually how little you are reducing nitrates with small water changes when you have high nitrates.

3) Make sure makeup water is pure. Phosphates and nitrates are often found in tap water. Phosphate and nitrate test kits will show if your tap water is contributing to your algae problem. If phosphate and nitrate levels are more than 0 ppm (some tap water measures out at over 50 ppm nitrate), filter the water through a RO/DI unit before using it as makeup freshwater or as source water for saltwater changes, or purchase RO water from a vendor.

4) Add additional detritivores to your cleanup crew. If excess food isn't eaten, it will decay and add to the nutrients and waste in the tank, as will the steady accumulation of detritus and mulm in an aquarium. More microhermit crabs, Nassarius snails and cleaner shrimp will help ferret out any uneaten Mysis and clean up detritus before it breaks down and enters the nitrogen cycle to eventually end up as excess nitrate.

So if you're having a problem with nuisance algae, consider bolstering your cleanup crew with additional snails and/or micro-hermit crabs that eat slime algae and other types of nuisance algae. Astrea snails, red foot moon snails, and Scarlet reef hermit crabs (Paguristes cadenati) all fit the bill and would be good additions in that regard.

Under the circumstances, Lora, the first thing that I would suggest trying is biological control in the form of additional aquarium janitors that have a special fondness for Cyanobacteria and hair algae. I recommend augmenting the cleanup crew for your seahorse tank with scavengers that specifically like to feed on the cyanobacteria or red slime algae, Lora. Especially good for this are the Banded Trochus Snails and Tiger Sand Conchs that are available from Aquacon (http://www.aquacon.com/snails.html) and the Mexican Red Leg Hermit Crabs (Clibanarius digueti) and certain Cerith snails (i.e., Cerithium strercusmuscarum), which you can get from GARF at the following website (just copy the following URL and paste it in your Web browser and then press "Enter," Lora -- that will take you directly to the right site):


They cost just a few dollars apiece and I would recommend getting one Tiger Sand Conch plus a good half-dozen Banded Trochus Snails and one or two of the Mexican Red Leg Hermits plus a handful of the Cerithium strercusmuscarum snails, depending on how severe the problem with the slime algae and hair algae has become. (However, you should not need any of the Live Sand Activator.)

So it would make good sense to bolster your cleanup crew with additional snails and/or micro-hermit crabs that eat red slime algae and green hair algae. Astrea snails, red foot moon snails, and Scarlet reef hermit crabs (Paguristes cadenati) or other seahorse-safe scavengers that all fit the bill and would be good additions in that regard.

Introduced as soon as possible to a new aquarium, as soon as the ammonia and nitrite levels are safe, Astrea snails effectively limit the development of all microalgae. In other words, they are good at eating diatoms, but will consume red slime and green hair algae as well. The Scarlet Reef Hermit Crab (Paguristes cadenati) is a colorful micro-hermit that's a harmless herbivore. So cannibalism isn't a concern at all for these fellows, nor are they likely to develop a taste for escargot. As hermits go, most of the time the Scarlet Reefs are perfect little gentleman and attractive to boot. I even use them in my dwarf seahorse tanks. Best of all, they eat all kinds of algae, including nuisance algae such as red, green and brown slimes, as well as green hair algae.

And, as we've already discussed, Mexican Red Leg Hermit Crabs (Clibanarius digueti) and certain Cerith snails really like to eat cyanobacteria or red slime algae. Garf (http://www.garf.org/redslime.html) offers a Reef Janitors package with hermits (chibanarius or clibanarious digueti, mexican dwarf hermit) and the snail (Cerithium strercusmuscarum), which are said to do an excellent job of cleaning up red slime algae.

5) Introduce macroalgae to consume excess nutrients and nitrates. If regular pruning is done, fast-growing Caulerpa will maintain its color and high growth rates without going sexual. Better yet, an algal filter or "algae scrubber" can be established in a sump or refugium.

6) Chemical controls. Phosphate absorbers (e.g., Phos-Zorb) Can remove excess phosphates, and Poly Filter pads can help absorb excess nitrates, changing color as they do so, which helps indicate= when the Poly Filter needs to be changed. Low ash activated carbon that is free of phosphates will also help remove such nutrients if it is change religiously and replaced with new carbon.

7) Controlled addition of food to tank. Don't broadcast feed, scattering Mysis throughout the tank. Instead, target feed your seahorses or use a feeding station. Don't overfeed, cleanup leftovers promptly, and observe fast days religiously. Thoroughly rinse your frozen Mysis before enriching it, since these shrimp juices that accumulate when the Mysis thaws can be rocket fuel for nuisance algae.

It is especially important for seahorse keepers to rinse the excess shrimp juice from the frozen Mysis you prepare before you feed it to the seahorses, and as long as it's just a quick rinse then it really doesn't matter if it's RO water or saltwater from the tank or even ordinary tap water that you use to gently rinse it. But that could rinse of the thawed frozen Mysis can pay big benefits for the home hobbyist by removing excess shrimp juice before the Mysis is fed to the seahorses because those shrimp juices are like rocket fuel for nuisance algae, stimulating rapid growth of hair algae or cyanobacteria (red slime algae).

8) Eliminate dead spots and increase the water flow in areas where the nuisance algae tends to grow.

9) Maintain the pH, calcium levels, and alkalinity of the aquarium in the proper range. Monitor alkalinity or carbonate hardness and the calcium levels in the tank as well as the pH.

10) Replace your aquarium lamps regularly to assure that the spectrum of light they put out favors the growth of coralline algae and macroalgae. (Over time, as bulbs age, they begin to put out light shifted more towards the red-end of the spectrum, which encourages the growth of hair algae.)

11) Reduce the photoperiod in your aquarium is much as possible to cut down on the light that's available for photosynthesis.

12) Increase the circulation in the aquarium to eliminate dead spots, particularly in the areas where the red slime algae or hair algae tends to grow.

13) Physically remove as much of the nuisance algae as possible. Some aquarists go as far as to remove all of the live rock from the aquarium and painstakingly scrub it free of the hair algae or even boil it to rid it of the nuisance algae, but boiling it also destroys the beneficial nitrifying and denitrifying bacteria it houses.

Okay, Lora, those are some additional suggestions to keep in mind whenever you are dealing with an outbreak of nuisance algae. I know that you are probably already well aware of most of the suggestions and that all of them may not apply to your seahorse tank, but they may give you an idea or two that can help.

For more information, check out the following online articles which are loaded with additional tips and suggestions for controlling outbreaks of nuisance algae. Please read these carefully, since they'll give you many more good ideas for combating your problem with hair algae:



Click here: GreenAlgContFAQs

Click here: Reeftank.com - Articles - Reeftank Maintenance - Algae Control FAQ

in addition to the URLs with useful information on controlling green hair algae listed above, Lora, I will also attach a document to this email which includes a comprehensive list of all the water quality parameters that marine aquarists should monitor in order to maintain optimum water quality at all times, including why they are important and how to adjust them upwards or downwards as necessary. Please download this document, save it on your computer, and then read through the information at your convenience.

Best of luck eliminating the green hair algae from your seahorse tank once and for all, Lora.

Pete Giwojna, Ocean Rider Tech Support

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