Diving Dad:

Pete Giwojna

Diving Dad:

I think you’re taking the right approach to dealing with your red slime algae (cyanobacteria) problem, sir. In addition to monitoring your water quality more closely, and performing frequent partial water changes to keep your water quality up to snuff, I would recommend employing some biological control methods to push you over the top and assure victory in your battle against the dreaded slime algae.

There are number of snails and micro hermit crabs that do very well with seahorses that include red slime algae and their natural diet, and adding a nice assortment of these algae-eating aquarium janitors to your arsenal will help you to eliminate the remaining cyanobacteria. I will discuss a number of these beneficial red slime eaters for your cleanup crew later in this message, Dad.

In the meantime, I fully agree that it’s best not to resort to the chemical warfare to knock out the red slime algae. The problem with such products is that they usually work very well initially, and the red slime algae will disappear at first, only to return with a vengeance after several weeks. The second time you resort to the chemical control product, it will be much less effective, and the Cyanobacteria will quickly become resistant to it, making it useless thereafter.

Under the circumstances, Dad, 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. I recommend augmenting the cleanup crew for your seahorse tank with scavengers that specifically like to feed on the cyanobacteria or red slime algae.

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


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

So it would make good sense to bolster your cleanup crew with additional snails and/or micro-hermit crabs that eat red slime algae. Astrea snails, red foot moon snails, and Scarlet reef hermit crabs (Paguristes cadenati) are some 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.

Likewise, 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.

Here’s hoping that your problems with Cyanobacteria are soon nothing more than a distant memory.

As for the dusting of cyanobacteria that has taken hold on your seahorses, I agree that is probably best just to ignore it, sir.

Algae often grows on the exoskeleton of seahorses, typically on their head and neck which are closest to the light source, particularly when they are kept in reef tanks with high-intensity lighting. In most cases, that’s perfectly normal and nothing at all to be concerned about. Seahorses often encourage algae to grow on them as a protective device to enhance their camouflage, and it’s usually best simply to ignore any such growth.

We are all well aware that seahorses can change color to blend into their backgrounds, and that Hippocampus is capable of growing or shedding dermal cirri, which are long filaments and branching extensions of its skin, as called for in order to match its immediate environment. To complete its disguise, the seahorse allows algae, bryozoans, hydroids, and other encrusting organisms to grow on its body, thereby rendering it all but invisible in its natural habitat. In fact, its skin contains polysaccharides which are believed to encourage algal growth, thereby helping it disappear into its surroundings. This vanishing act is so convincing that, even when they are collected by hand seining, seahorses often go undetected amidst the plant matter that accumulates in the net. Unless the collector is really diligent, he will lose a large proportion of his catch simply because many specimens will be overlooked and thrown back with the debris. In short, it’s perfectly normal for algae to grow on seahorses.

The seahorse’s pliant skin or integument is of course its first line of defense against disease. It contains mucus glands, and the slime covering the skin acts as a barrier to ectoparasites and infection. The protective slime can contain antibodies and antibacterial substances, and excessive mucus production is often the first sign of an infection or parasite problem. On the other hand, healthy seahorses often have small bright dots on their heads and torsos, which are actually mucus deposits. These beads of mucus glisten like little diamonds and are a sign of vibrant good health. When handling a seahorse, it’s important to wet your hands first in order to avoid removing too much of the protective slime coat.

So feel free to try very gently brush and away the algae as long as you take the necessary precautions and don’t disturb your seahorses’ protective slime coat any more than necessary, but you should be aware that the algae is likely to regrow if you don’t also address the conditions in your aquarium that are promoting the algae growth. This may mean adjusting your photoperiod or changing the type of lighting you are using, or eliminating any phosphates or nitrates that may be encouraging the growth of nuisance algae.

If you’re going to attempt to remove the excess algae growth from your seahorses, darkening the aquarium for a few days beforehand will make the algae easier to remove. Just leave the aquarium light off for a few consecutive days and that itself can be a big help. The seahorses will get along just fine with the ambient room light in the meantime, but the algae that is growing on it will begin to die back somewhat, and that makes it much more simple to brush away and remove.

In short, if you find the algae growth to be unsightly or your seahorses find it to be irritating, it can be very gingerly brushed off using a soft camel’s hair artist’s paint brush. Go to a craft store and select a few of the camel’s hair paintbrushes of appropriate size. Remember to wet your hands beforehand and observe the following precautions when handling the seahorses:

When handling seahorses, I do not like to use an aquarium net to transfer or manipulate my ponies, since their delicate fins and snouts can become entangled in the netting all too easily. I much prefer to transfer the seahorses by hand. Simply wet your hand and fingers (to avoid removing any of the seahorse’s protective slime coat) and scoop the seahorses in your hand. Allow them to curl their tail around your fingers and carefully cup their bodies in your hand to support them while you clean them with a soft bristle brush.

Composed of solid muscle and endowed with extraordinary skeletal support, the prehensile tail is amazingly strong. Indeed, large specimens have a grip like an anaconda, and when a 12-inch ingens or abdominalis wraps its tail around your hand and tightens its hold, its vise-like grip is powerful enough to leave you counting your fingers afterwards!

In fact, it can be quite difficult to remove an attached seahorse from its holdfast without injuring it in the process. Never attempt to forcibly detach a seahorse from its hitching post! When it feels threatened, it’s instinct is to clamp down and hold on all the tighter. When you must dislodge a seahorse from its resting place for any reason, it’s best to use the tickle technique instead. Gently tickling the underside of the tail where it’s wrapped around the object will usually induce the seahorse to release its grip (Abbott, 2003). They don’t seem to like that at all, and will quickly let go to move away to another spot. Once they are swimming, they are easy to handle.

Okay, that’s the lowdown on carefully brushing excess algae growth away from your seahorses. If it is done very carefully and gently, it will do the seahorses no harm other than the temporary stress of being handled while you are manually removing the algae.

However, simply brushing away the excess algae growth is often not the best option. Handling seahorses to remove the algae is always somewhat stressful for them, and as long as the conditions in the aquarium are the same – with the lighting unchanged and elevated levels of nitrates and/or phosphates still present to fuel the growth of nuisance algae – the unwanted algae is apt to grow right back again before you know it.

So you may want to downgrade your lighting or reduced the number of hours of daylight you are providing for the ponies in order to discourage the algae from regrowing right away.

At the same time, make sure you keep the nitrate levels and phosphate levels in your aquarium as low as possible to discourage the growth of film algae, Dad, and you should be able to control the algae growth. Let me know if you need any suggestions regarding the best way to eliminate excess nitrates are phosphates from your aquarium and I’d be happy to provide you with some specific recommendations in that regard that will allow you to quickly get your nitrates and phosphates down to insignificant levels.

For instance, Natural Nitrate Reducer is often able to bring nitrate levels down to zero over a period of several weeks when it is used according to directions.

Best wishes with all your fishes, sir.

Pete Giwojna, Ocean Rider Tech Support

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