I’m sorry to hear about the symptoms your seahorses have developed, sir. If you can provide me with more information about your seahorse setup and its inhabitants, as well as the current water quality parameters, I may be able to provide you with a better diagnosis of your problem and a more effective treatment regimen for resolving the issue. It would be helpful to know the size of your seahorse tank and the type of filtration you are using, as well as to have a list of all of the current aquarium inhabitants (fish and invertebrates). If you can provide me with your current readings for water temperature, pH, specific gravity or salinity, and the levels of ammonia, nitrite, and nitrate, I can advise you if anything needs to be adjusted to better suit the needs of your seahorses.
In the meantime, the following information on the use of formalin should answer your question in that regard, sir.
Formalin can be useful in treating fish with the following clinical symptoms:
Increased respiration; loss of normal body color; presence of discrete white spots (freshwater or saltwater "ich"); white areas on the body with circumscribed, reddish perimeter (Epistylis and/or bacterial infection); scratching on tank bottom or objects, lethargy, white cottony tufts or strands on body (fungus); dust-like, "peppered", yellowish spots on body surface (Oodinium); whitish skin slime or filmy body covering or patches (columnaris disease); disintegrating fins or fin edges (fin rot); mouth "fungus" (bacterial infection); pustules, furuncules or ulcers.
If any of the above symptoms are similar to the problems you’ve noticed with your seahorses upon close inspection, then administering formalin baths to the seahorses may be helpful, mermaid. Formalin 3 by Kordon is the medication I prefer for these treatments.
Formalin (HCHO) is basically a 37% solution of formaldehyde and water. It is a potent external fungicide, external protozoacide, and antiparasitic, and is thus an effective medication for eradicating external parasites, treating fungal lesions, and reducing the swelling from such infections. It is a wonder drug for treating cases of Popeye caused by trematodes, and also eradicates external nematodes.
In my experience, provided it is administered properly, seahorses tolerate treatment with formalin very well at therapeutic dosages. For a long term bath the correct dose is 15 to 25 mg/L. [Note: 25 mg/L equals 1 ml (cc) of 37% formalin per 10 gallons of water.] This is done every other day for 3 treatments.
For a short term bath (dip) the correct dose is 250 mg/L. This would equal 1 ml (cc) of 37% formalin per 1 gallon of water. This should be for about 45 minutes to 1 hour. In my opinion, formalin is a safe, effective treatment for parasitic infections in seahorses providing you don’t exceed these dosages and observe the following precautions for administering the medication properly:
Many commercial formalin products are readily available to hobbyists, such as Kordon’s Formalin 3, Formalin-F sold by Natchez Animal Supply, and Paracide-F, sold by Argent go to top Chemical Laboratories. Or whatever brand of formalin is available at your fish store should work fine, Pam.
A formalin bath simply involves immersing the seahorse in a container of saltwater which contains the proper dosage of formalin for a period of 30-60 minutes before transferring it to your hospital tank. Include a hitching post of some sort in the container and follow these instructions: place the fish in a three-gallon bucket or a similar clean, inert container containing precisely one gallon of siphoned, aerated tank water. Medicate the bucket of water with with the appropriate amount of formalin for a concentrated bath according to the directions on the label. Place an airstone in the bucket and leave the fish in the bath for 30 minutes. If at any time the fish becomes listless, exhausted or loses its balance, immediately place the fish in clean, untreated water in your hospital tank.
I want you to be aware of these precautions when administering the formalin bath:
Formalin has limited shelf life and degrades to the highly toxic substance paraformaldehyde (identified as a white precipitate on the bottom of the solution); avoid using any formalin product which has such a precipitate at the bottom of the bottle.
Formalin basically consumes oxygen so vigorous aeration must be provided during treatment.
Time the bath closely and never exceed one hour of chemical exposure at this concentration.
Observe the seahorse closely during the bath at all times, and it show signs of distress before the allotted time has elapsed, remove it from the treatment immediately.
If you can obtain Formalin 3 from Kordon at your LFS, Hanin, these are the instructions you should follow for your formalin dip:
METHOD 2 (DIP) FOR THE PREVENTION OR TREATMENT OF FISH DISEASES
(a) To a clean, non-metallic container (i.e., a plastic bucket), add one or more gallons of fresh tap water treated with Kordon’s AmQuel . For marine fish use freshly prepared saltwater adjusted to the same specific gravity (or salinity) as in the original tank. Make sure the temperature in the container is identical to that in the aquarium
(b) Add 1 teaspoons of Formalin•3. This produces a concentration of 100 ppm. formaldehyde.
(c) Agitate the solution with an airstone and adjust for a moderately strong flow of air.
(d) Remove the fishes to be treated and deposit them in the container for a treatment period of not more than 50 minutes. Immediately after the treatment period, or if signs of distress are noted, remove the fishes to a previously prepared recovery tank. The fishes may be returned to their original tank, but the presence of the original disease-causing agents in the tank water may result in a reoccurrence of the disease condition.
(e) Observe recovering fishes. Make sure that tankmates do not molest them during recovery.
(f) Repeat treatment as needed, every week. Each treatment is very stressful to the treated fishes. Do not reuse the dip solution.
For additional information on treating fishes with Formalin 3 by Kordon, see the following web page:
Click here: KPD-54 Formalin-3
If you get another brand of formalin, just follow the instructions that it comes with for a concentrated bath or dip (not prolonged immersion or a long-term bath) or follow the following directions, courtesy of Ann at the org:
FORMALIN Short-Term BATH Dosage and Preparation Instructions
Active Ingredient: 37% Formaldehyde
Indication: external parasites
Brand Names: Formalin, Formalin-MS
1. Do NOT use Formalin that has a white residue at the bottom of the bottle. White residue
indicates the presence of Paraformaldehyde which is very toxic.
2. "Formalin 3" by Kordon contains only 3% Formaldehyde. Dosing instructions will need to be modified if using this product.
• Fill a small tank with aged, aerated, dechlorinated marine water. Match the pH, temperature, and salinity to that of the tank the Seahorse is currently in.
• Add an artifical hitch and 1-2 vigorously bubbling airlines. Formalin reduces dissolved O2 so heavy aeration is required.
• Add 1ml/cc of Formalin per one gallon (3.8 liters) of tank water. Allow several minutes for the Formalin to disperse.
• Place the Seahorse into the dip water for 45-60 minutes unless it is showing signs of an adverse reaction. If the Seahorse cannot tolerate the Formalin dip, immediately move it back to the hospital tank.
• Observe the Seahorse for 24hrs for signs of improvement.
Please get back to me with the additional information I requested above, and we can go from there, sir.
Pete Giwojna, Ocean Rider Tech Support