Reptile & Amphibian Forums

I have been feeding my caimen fish and
after a few minutes they all seem to float
to the top dead. Why is that? Does water
temp have something to do with that? The
water temp is about 84 degrees. How do you
keep the fish alive?

Thanks,
jd4_42

There are a couple of reasons, that come to mind. The temperature can be a factor, if the fish are from a cooler water temp. They can go into shock from the sudden change. Another factor can be a high ammonia level in the water. Crocodilians can put out high fecal and urine loads. Even if you have a filter running, most of these are designed to handle smaller amounts produced by fish. If your tank has a gravel substrate, it can be even harder to keep clean. My 4' Caiman came to me with some snout damage and a bit of mouth rot around a couple of teeth. I have a filter running on her tank, but I still change the water completely twice a week. This cleaner water is clearing up the problem. A filter can be deceiving. The water can look cleaner than it is.

I would check these things first. A crocodilian tank is definitely not a easy environment for a fish, but they should be able to survive until they are eaten. If they are coming to you in a colder water, you can keep them in a separate tank or bucket, until feeding time. This would allow their water to acclimate to room temp.
Hope this helps.
JeffP

In addition to thermal shock as Jeff mentioned, another thing that will kill them very quickly is chlorinated water. Even the low amounts of chlorine in tap water will burn the sensitive gills of the fish, that's why people who keep fish always neutralize the water with drops using products such as Novaqua or other products available at pet stores.
As to the thermal shock, one way to combat that is to just let the plastic bag or other container that the fish come in to float in the water that they are going to be placed in. This will allow the water temperatures equallize providing a gradual warm up for the fish so they don't go into shock.

Bill

In addition to floating the bag of fish to equalize the water temps, you can take a few other precautions..

Open the bag after floating it for 10-15 minutes - Add one cup of water from your caiman's tank. Float the bag for another 5-10 minutes.

Do this as much as you feel necessary, to slowly acclimate the fish to the different water.

Also - it could be an oxygen problem... An air stone will help your water quality all around, so it may not be a bad idea.

I agree that floating is a reliable way to acclimate fish to an aquarium, but my fear would be that the floating bags would be attacked. Most crocodilians become excited or curious of any new items brought into their world. I'm not sure how long the bags would be safe, once the fish were noticed.

JeffP

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