*Salvage protocol for treating very sick fish*


Dr. Fish
Navarre, FL
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Reposted with permission. @alprazo

Salvage protocol for very sick fish.

Almost daily I read a post from someone describing a fish sick from either ich or velvet and can predict that it will not make it to the morning.

There are several techniques that can be employed to reduce the metabolic demands on the fish, reduce stress, decrease the damage from its immune response and possibly keep the fish alive until you are able to eradicate the parasite.

1. Decrease the temperature to 72F for most tropical fish.

2. Decrease the salinity to 1.017 or lower

3. Increase the oxygen saturation to greater than 150% by the addition of pure O2.

4. Turn the lights off

5. Intramuscular injection of dexamethasone at 0.5 mg/kg

Though I have never used all of these techniques together, I have used them all and have been surprised to find that fish swimming the following morning. These are recommendations and should be adjusted to the situation.


Dr. Fish
Thread starter
Navarre, FL
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Another relevant post from @alprazo:

I just wanted to comment on velvet. It has an ability to infect like no other, the lethality is extremely high and the course is surprisingly fast. It probably has caused more people to leave the hobby than any other disease with total wipe outs within days of exposure. Often it is too late once you even think your fish may have it. That said, with practice and experimentation, I have learned how to save many fish from even late stages of it disease.

Velvet kills like ich, another other single celled parasite, by causing inflammation and eventually edema (swelling) of gills. The thickened gill inhibits oxygen exchange. The fish breathes faster and harder in an attempt to increase the exchange, but in doing so, metabolism increases as fish demands more oxygen. This viscous cycle ends by the fish fatiguing and finally suffocating or having a heart attack due to lack of oxygen and tremendous cardiac strain.

Several steps can be taken to break this cycle and salvage the fish.

First it is important to decrease metabolic demand and this can be done by:

- Decreasing the temperature - I shoot for 70 or lower over several hours.
- Decreasing the Specific Gravity to 1.015 (can be done immediately)

Next you want to increase the oxygen saturation in the water. This will promote better exchange. I aim for a 200% dissolved oxygen level with my YSI DO meter. (Measurement is not 100% necessary).

- Pure oxygen is easily bought from either a welding supply store or a medical supply house. Oxygen is cheap and useful for several applications like power outages and transporting. You also want an airstone that produces a superfine bubble. They are typically made for pure gas and have warnings about using air.
- Temperature reduction - This not only reduces metabolism in the fish, but it will also increase the waters capacity to carry dissolved oxygen.

Edema reduction: Steroids

Just like giving a shot in the knee - it helps to reduce the swelling.

- Intramuscular dexamethasone with an estimated dose of 1-2 mg/kg into the muscle on the side of the dorsal ridge. (impossible to be precise in small fish)

I sounds difficult but it is not. A tuberculin syringe with a 27 gauge needle to draw up the solution and a 30 gauge needle to inject.

Following the above protocol, I have witnessed more than a couple of fish recover from assured demise.

I also recommend treating with chloroquine. Formalin unfortunately is an irritant and theoretically could worsen the gill edema.

BTW - the same protocol can be use with ICH.