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FAMA Forum - October 2002
I am planning on setting up a ten-gallon tank for dwarf seahorses and I have heard a lot of different recommendations for substrate. Some people have mentioned that a bare-bottom tank is best, while others recommend crushed coral or sand. Would you give me your opinion on what you feel is best?
This is a very common question that many new seahorse hobbyists ask and I am very glad you have asked me this. I will try to clarify some of the pros and cons of different types of substrate.
Over the years I have tried many different types of substrates. I have even maintained a bare-bottom tank for a while and I cannot say for certain that I had encountered any real side effects with any of the methods, but there are some considerations to keep in mind. Firstly when you are planning to keep dwarf seahorses, you want to select a substrate that is both beneficial and attractive. Substrate does have an important role in maintaining good water quality conditions. You also want to provide a safe atmosphere for your one-inch miniature seahorses. For this reason I highly discourage the use of live sand. Although live sand can provide some wonderful life and provide the beneficial bacteria’s for a saltwater tank it can also house some critters that may be harmful to dwarf seahorses and their fry. This is also true for live rock. Your sand will become live during the natural process of cycling, thus providing your tank the needed life to break down waste.
I would also try to avoid crushed coral because of the large sized grains and the amount of space between each grain. With plenty of free space between the grains of substrate a lot of waste material will collect resulting in poor water quality and unsightly hair algae. It can also be difficult to observe any fry death that may occur in your tank. Crushed coral is also very abrasive and can actually damage the tails of seahorses that enjoy hunting on the substrate. This can also cause an infection that may inevitably kill your seahorse. Normally however, this type of problem does not occur with the dwarfs because they do not generally drag their tails along the bottom, but this is not a set standard rule and I have observed some dwarfs that do slide across the substrate.
Bare bottom tanks can be fine with strict tank management. Substrate is a very beneficial part of a healthy tank. Most detritus breaks down in the substrate where your biological filtration is established, thus helping keep keeping your tank healthy. If you are planning on a bare bottom tank, a second filter may be required to keep up with the biological load along with more frequent water changes and closer monitoring.
I find that sugar-sized sand makes the best substrate for your dwarf tank. These types of grains are usually a lot smoother and can easily pass through the gills of your seahorse if sucked up. This type of substrate also naturally aids in the reduction of nitrates in your tank. The less space between the grains means less places where detritus can collect and the healthier your tank becomes.
About a year ago I started using black sand. I find this to do very well in the tank. The seahorses are more noticeable and their colors seem brighter. I also find it much easier to see their fry and I am able to easily see any fry that may have expired.
Choosing a substrate is a personal choice. What works in one tank may not in another. I have worked with all of the above and I have not encountered any significant problems. As long as you are aware of the differences and possible risks, you can select a substrate that best suits your needs.
I saw the American Pacific Seahorse (Hippocampus ingens) display at the Steven Birch Aquarium in San Diego California. Since they are native to the Americas and are so exotic and majestic I would like to add a pair to my sea horse tank, but I am worried about the temperature. I keep my tank at 78- 80 F, but the Pacific Sea Horse display at the Birch Aquarium is at about 62F. Will my tank be too warm for them? If not, why does Birch Aquarium keep them at such cool temperatures? Are they really tropical seahorses or are they more of temperate fish? Do I need to keep them at cooler temperatures than I keep my aquarium right now and if so how cool? Will I need to buy a chiller?
Thanks, Samantha from Clairemont
The Pacific Sea horse (Gigante) is a very beautiful and majestic seahorse indeed! I can see why you would want to add a pair to your tank. I can also see why you are confused about their temperature requirements. Lets take a look at their natural home ranges and the corresponding ocean temperatures from which the come. This will help you to see that this sea horse is a truly tropical and highly social species!
Their geographic range extends from the coastal waters as far North as San Diego during El Nino years and as far South as the Galapagos and northern Peru. Peru is slightly south of the equator where as Galapagos and Ecuador straddle the equator!! The ocean temperature here averages from 80F to 82F! The H.ingens range then extends from here up the coast along the Pacific side passing by the Western coast of Columbia (approximately 1-7 degrees latitude), Panama (approximately 7 degrees latitude), Costa Rica (approximately 8-10 degrees latitude), Nicaragua (approximately 10 degrees latitude), El Salvador (approximately 10 degrees latitude), Honduras (approximately 10 degrees latitude) and Guatemala (approximately 14-15 degrees latitude). This whole area has some of the warmest ocean waters on the planet. Warm equatorial currents flow here all year around with the average ocean coastal temperatures being between 82F and 84F and increasing to as high as 90F during the summer (our winter)!! All very hot places with bathtub like ocean temperatures. This is the main range of this species with coastal waters also being a very very rich nursery area for Penaeid Shrimp larvae! In fact, the H. ingens (like many sea horse around the world) is a by catch brought up by local fisherman trawling for shrimp in mostly small wooden pongas (canoe like boats) but also in larger commercial trawlers. At one time theses sea horses were so plentiful and so easy to collect that millions of H ingens were heavily harvested annually for the Chinese medicine market. Now, of course there just are not that many left.
The range now extends into Mexico with a latitude between15-20 degrees. These coastal areas are more familiar to most North Amercians from the large tourism industry. The waters here are still very warm most of the year but do start to cool during the winter with typical ranges being from 72F to 80F. Now we reach Baja California and San Diego (30-32 degrees latitude) where H. ingens has been occasionally seen during the El Nino years. Normally the average temperature of San Diego is a chilling range of 55F to 65F with the warmer temperatures lasting a few brief months in August and September. During El Nino years the warmer currents that originate off equatorial Ecuador push further north than normal bringing the high temp up to as high as 72 to 75!! This happens on the average once every 4 years. It is during these brief moments that the Pacific Sea Horse has been seen in southern California. There may even have been and occasional sighting further North but this is not their typical home range.
Now it is true that sea horses have an amazing ability to adapt to temperatures different from their native waters. although it may affect their color, activity level and general health and longevity. The Pacific Sea horse (and many other species as well) is one that has adapted fine to these cooler temperatures.
The reason that Public Aquariums use cooler water is simple…..it costs a lot of money to heat salt water especially when using high volumes like most Aquariums do. If the species in question can adapt well to cooler temperatures and it does not adversely affect the health of the animal this is not a problem. It saves the aquarium a lot of money.
Most Aquariums around the world are located in temperate areas where the ambient ocean temperature from which they pump their water is around 50F to 55F or cooler!! They just cannot afford to heat water at all or any more than absolutely necessary. Adjusting the temperature in any way different from the ambient sea from which they pump their seawater if they are lucky enough to be on the coast is an expensive proposition. If they are located far away from the coast and must make their own seawater the cost of heating is an extra expense that adds to an already highly costly reciruclation process.
For the home aquarist the situation is the reverse. It is extremely expensive for the hobbyist to cool seawater. It is least expensive to keep your tank at your house ambient temperature, which for most of us is about 75F or to heat a little bit up to 78F with a simple heater during the winter months.
So you can put the Pacific Sea Horse in a cooler tank (60-65F) with a chiller if you want too after a very very careful and slow acclimation but it is not their ideal temperature as they are not temperate fish. You will not see their magical colors and they will be much less active than normal. These Gigante sea horses are true tropical dwellers! Not only do they like it warm but they have big appetites and they are very social!! You will see beautiful tropical colors and a truly happy and active sea horse if you can keep them in herds and at temperatures from 75 to 80F!! There is no need for a chiller, that is for sure!!
I have recently started keeping a dwarf seahorse tank and 2 days after I have observed a male courting a female he started floating at the top of the water. I did notice that he was holding onto an airline stone and I remember reading something along of the lines that bubbles can get trapped in male’s pouches. Should I be worried or is he just pregnant. If he does have air bubbles in his pouch how do I get rid of them? He is eating, but he just cannot seem to hitch onto anything.
You are very correct that air bubbles can become trapped inside a male’s pouch and I am sure this happened while he was hitched onto the airline. During their courtship displays a male will open his pouch and pump water in and out. He does this to prepare his pouch for pregnancy and to show his potential mate that he is indeed ready to be a proud father. Seahorses also enjoy the stimulation from air bubbles occasionally, just as we sometimes enjoy a nice relaxing moment in a Jacuzzi. The problem occurs when the male has his pouch opened while he is near the bubbles. They can get trapped inside of his pouch, which will lead to buoyancy problems. The first step to prevent this from happening is to remove the air stone or device that is emitting the air bubbles or you can modify it so that the air bubbles are released toward the top of the water. I would also use something that puts out larger bubbles instead of smaller bubbles.
There are other ways that can lead to air bubbles inside the males pouch. Poor water quality and insufficient tank depth can pose problems as well. During courtship and pumping (when the male inflates and deflates his pouch) the male is not only trying to impress his intended mate, he is also flushing his pouch to cleanse out any debris that may be inside his pouch. Poor water quality and debris may cause a gaseous buildup and insufficient tank depth can prevent the male from thoroughly cleansing his pouch, thus leading to trapped air bubbles inside of his pouch. Air bubbles caused by these problems are often chronic leading the hobbyist to pouch burping (the process of evacuating the trapped air bubbles) often. It is not unusual to find a hobbyist burping a seahorse prone to this condition more than once a week. Luckily this is generally not an issue for dwarf seahorse enthusiasts as most of the tanks exceed the minimum requirement of three times the height of the seahorse. It is important however to always maintain optimum water quality and this includes regular tank maintenance and water changes.
Air bubbles inside the males pouch or pouch emphysema can lead to secondary problems. Starvation can occur from the inability for the seahorse to catch its food and infection can occur if not treated properly. If you have a seahorse that does have air bubbles trapped inside of his pouch they must be removed. The most noninvasive way is recommended. To do this, you need to hold the seahorse underwater with your non-dominant hand. At first this will appear very awkward and intimidating. The seahorse will struggle. With your dominant hand, start from the bottom of the pouch from the tail and work upwards with a gentle massaging motion. Repeat this a few times using your thumb and index finger. Work in an outwards circular motion in such a way to force the pouch to open. There will not be a large opening and at this point you should see a few bubbles escaping from the pouch. The bubbles are very tiny and escape rapidly. You may also push inwards with your thumb and roll it upwards. Repeat this process until all of the bubbles have escaped. If you are successful he will be able to swim away normally. Your first tries may be awkward and it may take a few attempts, but after you have done this once or twice it becomes very easy.
The second method of pouch burping is more invasive, but with the proper tools this can be very safe and effective. A pouch kit from Ocean Rider is highly recommended for this and it is safe for dwarf seahorses as well as the larger seahorses. If you do not have a pouch kit, a clean, coated bobby pin can be used in a pinch, but it is not suggested. For this procedure you will hold the seahorse with your non-dominant hand. Insert the tip of the tool inside the opening of the pouch. The seahorse will struggle and it will feel awkward for you. The opening into the pouch is on the top part of the pouch and you should be able to see a small seam that indicates where the opening should be. Slowly push the tip until it is inside of the pouch and massage the pouch as best as you can with a free finger. This takes a bit of practice, but after you have done this it becomes very easy. You want to make sure that all of the bubbles have been evacuated. Once you feel they are all out, massage one more time to be sure. If you are successful your seahorse should be able to swim away completely normal. The stress is short lived and often right upon release they will hitch onto their favorite place and begin eating.
Prevention of pouch emphysema is best. Removing or modifying bubbles in the tank and maintaining optimum water conditions along with proper tank depth will help prevent this type of problem. Healthy tank-raised seahorses are your best option and they are less likely to get secondary illnesses related to stress. This will also help prevent hobbyist stress, which will leave you more time to enjoy your aquatic equine companions.
Can I keep the American Pacific Sea Horse in the same tank as other sea horses or do they grow so big that they need their own tank? If so, how big of a tank do they need??
Thanks, Eric from Memphis
Although the American Pacific Sea Horse (Gigante) is considered to be one of the largest living sea horses it does not need an exceptionally large tank. This is due in part because of growth limitations in home aquariums, to the details of their anatomy and their extremely slow growth rate, and due to their high level of domestication and adaptability.
As most of you know and as was reported by Dr. Clyde Tamaru in Horse Forum July 2001 issue sea horse growth is severely limited by tank size, diet and water conditions. Typically home aquariums are just not the environment that displays higher growth rates and therefore does not allow fish to reach their optimum size.
The sea horse grows very slowly once they get into your aquarium especially if it is a small tank. Typically they will not get that much bigger than the size it is at the time of purchase unless you put them in very large tank with a high water flow and feed them a highly nutritious diet! When they do grow it will be quite slowly comparatively speaking. So the chances of your Pacific Sea horse getting to the maximum size is slim and it will take a long time if it does. We have seen that our Gigantes live well over 6 years and keep growing daily but they are in very large systems with a tremendous amount of water flow and are being fed a diet fit only for Kings!!
When you purchase a Gigante he or she will be approximately 10 months old, sexually dimorphic and of a very nice home aquarium size of 6 inches, so there is no need to worry about creating a home for anything much larger unless you want to keep a large number of seahorses and you want them to reach their maximum height and weight quickly.
The Project Sea Horse group has reported an average length of 7.5 inches from 19 wild caught specimens whereas Ocean Rider has seen much larger animals as long as 12inches! The difference in reported sizes is most likely due to the fact that when a wild population becomes threatened the larger specimens are always the first to disappear and therefore are never reported in the literature.
It is also important to understand that sea horse lengths are measured from the tip of the crown on the head to the tip of the straight tail. So depending on the length of the tail you will loose several inched in height when the sea horse is hitched which is its most common position. The H .ingens is a slim and tall sea horse compared to the Mustang which is also tall but very broad. The Gigante is more like the Brazilian sea horse in its general appearance, color variations, behavior, slow growth rate and even fry size. They are obviously of very similar genetic background, which will be very obvious to you when they are side by side in your tank. The difference is that the Gigante does get larger and develops a very unique tail in that is like a strong muscle, which you may be able to experience for yourself when it wraps around your fingers! A full-grown Gigante can grip your hand like an octopus!!
In summary I would provide the Pacific Sea Horse with the same tank requirements that you provide for the Brazilian sea horse or the large Mustang. I would recommend a minimum tank height of 20 inches and volume of 25 gallons for 2 pairs. Ideal height would be closer to 28 inches and a volume of 55 gallons. In a set up like this you could easily put 4 or 5 pairs of Gigantes alone or mix them with other larger tropical sea horses! Don’t forget to use a protein skimmer with these guys as they have good appetites and should be fed twice a day!
Help! My dwarf seahorse tank has been thriving for the past 8 months and my herd is growing steadily as babies mature. I've been able to raise many of the babies from several broods during that time, but lately things have changed. For the past week or two, none of the babies survive more than a few days. They die off one, or two, or a few each day for no apparent reason until they are gone within a week. Now I am losing established adults too, three of them in the last week. No symptoms -- one day they seem fine, the next day they turn up dead. One was still hitched, its tail wrapped around a seahorse tree, as if it had just died in its sleep.
The only thing different I have noticed is a few tiny little swimming bugs, like silvery bubbles the size of the head of a pin. In fact, I thought they were air bubbles at first until I noticed they move in little bursts, a
herky-jerky pumping motion, when they aren't drifting or adhering to objects. Now I'm wondering if my seahorses could be eating these, mistaking them for baby brine shrimp? And if maybe they are poisoning my seahorses that eat them?
I've never seen them in my aquarium before until now, and I would never have noticed them now if I weren't examining the tank so closely, looking for a problem. Have you every heard of anything like this? Please help!
What you are describing to me sounds like hydroids. I find this to be the number one threat of dwarf seahorses and their fry. Unfortunately this is a very common occurrence in a dwarf tank. The atmosphere that our beloved fish live in provides a wonderful home for hydroids as well.
Hydroids are tiny colonial stinging animals that have 2 visible stages. They are generally first noticed in a collection of what appears to be pinkish colored algae. This is the polyp stage, a hydroid colony. They are often seen on the substrate, and any smooth surface in your tank. When they spread on your tank wall the stalks are often attached by what looks like a web. If you look closely you can see the buds of the medusa. The medusa is the free-swimming stage that you have described. They look like tiny jellyfish and move upwards in a jerking motion. When they are not in motion feeding they can be seen if you look carefully just sitting on the substrate or any surface they land on. You can also visualize them attached to the tank walls. When the medusa attaches itself to the tank wall they look like silvery stars. They will have a larger dot in the middle of them and smaller ones at the base of their nematocysts (the stinging protruding appendages). If you look even closer they will often resemble a snowflake. They are actually quite interesting to look upon, but they can be very deadly to their fellow tank mates.
An infestation of hydroids can occur in many ways. Quite often hydroids will arrive right along with your new herd of wild-caught seahorses. They can also hitch a ride from many of the tank mates and Caulerpa that come from the collector. You can also transmit hydroids from one tank to another by sharing supplies, moving fish, objects or anything that comes from a tank to another that may have hydroids. I have also seen an association of hydroids with brine cysts that have not been decapsulated. Under a controlled study I have been able to establish a healthy colony of hydroids from a clean tank and brine cysts. The realization that hydroids have invaded your tank is frightening considering the amount of damage they can do.
Hydroids feed vigorously on newly hatched brine shrimp; the slow current and warm water in a seahorse setup makes an ideal home for these potentially deadly animals. They repeatedly sting their prey, which often leads to death, especially for the fry, which are most vulnerable. Sadly, many hobbyists do not understand why all of a sudden their once healthy herd of seahorses starts to decline rapidly. Hydroids are very small and unless you are aware of what they are they can easily be overlooked.
Prevention is the best way to avoid getting hydroids. When possible purchase tank-raised seahorses such as the Pixies sold by Ocean Rider. Not only are they very healthy and hearty, but also they are free of hydroids and any unwanted organisms. Do not share equipment with any other tank without sterilizing the implements, and be careful where you purchase any Caulerpa and/or tank mates that will go inside the tank. Decapsulating your brine cysts are another easy way to help thwart hydroids from taking root. If you must purchase wild caught seahorses, you should always freshwater dip your seahorses for two to three minutes then keep them in a quarantine tank for three days, followed by another freshwater dip before you introduce them into their home. The same procedure should likewise be followed, as tolerated, with any tank mates. Caulerpa should be carefully rinsed with fresh saltwater if there are no obvious signs of hydroids. Snails and hermits should have their shells scrubbed with freshwater. If you are able to visibly identify hydroids on any of the tank mates and/or Caulerpa, they need to be discarded or placed into a separate tank.
If you have hydroids present in your tank the best way to get rid of them is to start a clean second tank with new substrate, decorations, hitching posts and anything else that will go into the tank. You do not want to add anything from the infected tank except your seahorses. The seahorses will need to be fresh-water dipped and placed into a quarantine tank for three days. You can break down the infected tank and sterilize everything with bleach solution. Any other tank mates need to go into another tank. You do not want to risk reinfestation in your new tank. Caulerpa, if you have any, needs to be disposed of.
A second method of hydroid extermination using a deworming product called Panacur is still in the testing stage. A dosage of 1mg per 1 gallon of water seems to be very effective in killing hydroids of all stages. This is not safe for most inverts or Caulerpa. Any live coral that you may have needs to be removed. I also remove the seahorses for three days as well, although this does not seem to affect them if they remain in the tank.
When setting up a seahorse coral, it is always best to get tank-raised specimens from a place that is hydroid free. Any seahorses and/or tank mates that are purchased from a reputable place like Ocean Rider ensures that your specimens will arrive clean and parasite free. Practice strict tank management and avoid adding anything into the tank that may be affected. Remember, just because you may not visibly see hydroids it does not mean that they are not present. You should always decapsulate your brine eggs. This not only helps ensure removal of organisms, but it also increases your hatch rate and time.