Re:Help with seahorses…

Dear turtlemama:

I’m very sorry to hear about the problems you’ve been having in the aftermath of tropical storm Fay. Few things can mess up an aquarium quicker than a prolonged power outage and I hope that you will be able to get everything back to normal again in short order.

My best bet is that the dissolved oxygen level in the aquarium is too low and the level of the carbon dioxide in the water is too high following the loss of power, and that your seahorses are struggling as a result. I would recommend increasing the aeration/oxygenation in your seahorse tank is much as possible and treating the seahorses with methylene blue to relieve their respiratory distress, as explained below.

Hypoxia due to low oxygen levels and/or or high carbon dioxide levels will cause lethargy and respiratory distress (huffing, panting, labored breathing, rapid respirations, etc.) in seahorses and can be fatal in severe cases. This often tends to happen overnight when CO2 naturally rises as O2 levels are dropping due to the reversal of photosynthesis and a loss of power or equipment failure cuts of the filtration and circulation in the aquarium.

As you know, while they are photosynthesizing during the day, zoanthellae and algae consume CO2 and produce O2, but at night, in the absence of light, this process is reversed and the photosynthetic organisms consume O2 and give off CO2 instead. So in a small, closed-system aquarium, dissolved oxygen levels are typically the highest and dissolved CO2 levels the lowest just before lights out when the aquarium lights have been on all day long. Likewise, dissolved oxygen levels are normally at their lowest and CO2 levels at their highest first thing in the morning after the aquarium lights have been off all night. (The drop in pH most aquariums experience overnight is directly related to the drop in dissolved oxygen levels and the rise in carbon dioxide levels that takes place during the night.) Seahorse setups in general are especially susceptible to such problems because hobbyists are so conscious of their seahorses’ limited swimming ability that they tend to leave their aquariums undercirculated. Poor circulation and inadequate surface agitation can lead to inefficient oxygenation and insufficient offgassing of carbon dioxide.

Seahorses are more vulnerable to low O2/high CO2 levels than most fishes because of their primitive gills. Unlike most teleost (bony) fishes, which have their gills arranged in sheaves like the pages of a book, seahorses have rudimentary gill arches with small powder-puff type gill filaments. Seahorses are said to have "tufted" gills because they appear to be hemispherical clumps of tissue on stems. Their unique, lobed gill filaments (lophobranchs) are arranged in grape-like clusters and have fewer lamellae than other teleost fishes. Because of the difference in the structure and efficiency of their gills, seahorse are unsually vulnernable to hypoxia when CO2 levels are high and/or O2 levels are low.

Most deaths due to hypoxia occur when the water pump or filter fails during the night, or there is a power outage overnight when the aquarist is unaware, cutting off the filtration, water circulation, and aeration of the aquarium with devastating results. I imagine that in Florida in August, the weather is likely to be pretty warm and that your house may have become hot when the air conditioning was lost during the power outage. Rising water temperatures in your aquarium as a result would further deplete the level of dissolved oxygen in the aquarium and exacerbate this problem.

Heat stress due to a summertime heat wave can rapidly deplete the oxygen levels in a poorly circulated seahorse tank. It’s important to remember that the warmer the water, the less dissolved oxygen it can hold. Elevated water temperatures increase the metabolism of your seahorses, and therefore their consumption of oxygen, at the same time that the rise in temperature is reducing the amount of dissolved oxygen in the water. That creates a dangerous situation for seahorses and may well result in respiratory distress and rapid, labored breathing, as well as contributing to asphyxia under certain circumstances. In my experience, the optimal temperature range for Hippocampus erectus in the home aquarium is 72°F-75°F, and they may begin to experience heat stress if the water temperature approaches 80°F

In short, turtle mama, I suspect that your seahorses are starved for oxygen and that is why they have been breathing really hard and have become so lethargic, even laying on the bottom at times. A lack of oxygen is very debilitating and leaves the seahorse very weak and fatigued. As a result, the affected seahorses may detach themselves from their hitching posts periodically and rest on the bottom, unable to exert themselves in their weakened condition. As you can imagine, being deprived of oxygen really wipes them out in terms of loss of energy and stamina. And it also results in respiratory distress, and rapid, labored breathing as they try to oxygenate themselves.

To counteract this problem, I would like you to add one or more airstones to your aquarium anchored a few inches below the surface. This will increase the aeration and surface agitation in the aquarium, facilitating efficient gas exchange at the air/water interface, and promote better oxygenation of the water. It will also help to gently increase the circulation in the aquarium, all of which will aid the seahorses breathing.

In addition, the seahorses would also benefit greatly from a dip in methylene blue, which would aid their breathing and provide them with some quick relief.

Here are the instructions for treating seahorses with methylene blue, turtle mama:

Methylene Blue

Commonly known as "meth blue" or simply "blue," this is a wonderful medication for reversing the toxic effects of ammonia and nitrite poisoning (commonly known as "new tank syndrome"). Since hospital tanks are usually without biological filtration, and ammonia and nitrite can thus build up rapidly (especially if you are not doing water changes during the treatment period), it’s a good idea to add methylene blue to your hospital ward when treating sick fish.

Methylene blue also transports oxygen and aids breathing. It facilitates oxygen transport, helping fish breathe more easily by converting methemoglobin to hemoglobin — the normal oxygen carrying component of fish blood, thus allowing more oxygen to be carried through the bloodstream. This makes it very useful for treating gill infections, low oxygen levels, or anytime your seahorses are breathing rapidly and experiencing respiratory distress. It is the drug of choice for treating hypoxic emergencies of any kind with your fish.

In addition, methylene blue treats fungus and some bacteria and protozoans. Methylene blue is effective in preventing fungal infections, and it has antiprotozoal and antibacterial properties as well, by virtue of its ability to bind with cytoplasmic structures within the cell and interfere with oxidation-reduction processes. A "must" for your fish-room medicine cabinet. However, be aware that it is not safe to combine methylene blue with some antibiotics, so check your medication labels closely for any possible problems before doing so.

If you can obtain the Kordon brand of Methylene Blue (available at most well-stocked local fish stores), the instructions for administering it as a very brief, concentrated dip are as follows:

For use as a dip for treatment of fungus or external parasitic protozoans and cyanide poisoning:
(a) Prepare a nonmetallic container of sufficient size to contain the fish to be treated by adding water similar to the original aquarium.
(b) Add 5 teaspoons (24.65 ml) per 3 gallons of water. This produces a concentration of 50 ppm. It is not recommended that the concentration be increased beyond 50 ppm.
(c) Place fishes to be treated in this solution for no longer than 10 seconds.
(d) Return fish to original aquarium.

When you administer such a dip, hold the seahorse in your hand throughout the procedure and time it closely so that the dip does not exceed 10 seconds.

And here are Kordon’s instructions for administering the methylene blue in a hospital tank if longer-term treatment seems appropriate to reverse more severe cases of nitrite poisoning and ammonia toxicity or exposure to high-level of nitrates:

As an aid in reversal of nitrite (NO2-) or cyanide (CN-) poisoning of marine and freshwater aquarium fishes:
(a) Remove carbon filter and continue to operate with mechanical filter media throughout the treatment period.
(b) Add 1 teaspoon of 2.303% Methylene Blue per 10 gallons of water. This produces a concentration of 3 ppm. Continue the treatment for 3 to 5 days.
(c) Make a water change as noted and replace the filter carbon at the conclusion of the treatment.

See the following link for more information on treating with Kordon’s Methylene Blue:

Click here: KPD-28 Methylene Blue
http://www.novalek.com/archive/kpd28.htm

Any well-stocked local fish store should carry methylene blue for aquarium use. If you obtain a brand of methylene blue other than Kordon, just follow the instructions the medication comes with. Remember that methylene blue will have an adverse impact on the beneficial bacteria that carry out the nitrogen cycle, so don’t use it in your main tank — rather, use the methylene blue as a quick dip or for treating the seahorses for a prolonged period in your hospital tank.

There is also another trick you can consider for raising the dissolved oxygen level in your aquarium quickly by adding a small amount of ordinary hydrogen peroxide (H202) at the right concentration to your aquarium. Hydrogen peroxide can be use as a treatment of acute oxygen insufficiency at a dose of 0.25 ml of a 3% H2O2 solution per litre of water, which is equivalent to adding 1 ml of a 3% hydrogen peroxide solution per gallon of water.

If you want to give this a try, you can prepare the hydrogen peroxide solution by taking one gallon of dechlorinated freshwater and then removing 10-oz of the water and replacing it with 10-oz of 35% hydrogen peroxide instead. (Note: 35% is the standard concentration of the ordinary hydrogen peroxide that you obtain at the drugstore or probably have in your medicine chest at home.) This formula will produce a 3% solution of hydrogen peroxide, and you can then add one millimeter of the 3% solution per gallon of water in your aquarium to increase the level of dissolved oxygen rapidly.

Remember to allow for the amount of water that is displaced by the aquarium substrate and decorations when calculating how many milliliters of a 3% hydrogen peroxide solution to add to your aquarium. Be careful not to exceed the recommended dosage since adding too much of the hydrogen peroxide can be harmful. This is a one time emergency procedure for use in a crisis situation — do not add any additional hydrogen peroxide to the aquarium after the first dose.

Best of luck getting your seahorse tank back to normal again following the power outage, turtle mama. Here’s hoping that your seahorses are breathing easier and feeling much better soon. It sounds like you have been doing very well with your seahorses thus far and I hope your success will continue after you overcome this problem.

Respectfully,
Pete Giwojna