Backyard Aquaponics
A place to discuss aquaponics

In my distress I posted this in the wrong forum initially.

My Channel Catfish seemed to be doing fine but now four are gasping at the surface, their skins are whitish and peeling. Nothing has changed in the management of the tanks recently.

Ok, a few things I observed: The problem seems to be in only one tank (I have two tanks of Channel Cats and two tanks of Bluegill, all connected); the pH of the system seemed low 6.5-6.8; that tank gets a lot of sun and we've been having warm temps.

I removed 4 dead Catfish from the visibly affected tank and did a partial water change using well water. I had previously only been topping off the system with rainwater. I sprayed the well water on the surface, trying to get a lot of aeration. Last I looked the fish were doing a little better, that is, not so many at the surface gasping (though it's possible they already gave up the ghost during the water change).

gasping at the top is usually an oxygen deficiency not sure about the whitish and peeling skin have you salted your system? and what are your other levels ammonia, nitrites and nitrates?

I don't have a test kit able to measure those things; I don't have any salt.

There is a lot of duckweed proliferating on the sunny tanks, not sure if that indicates anything....

I would suggest going and buying some salt then and salting the tanks, you can use pool salt aslong as its is pure seasalt we buy the stuff over here for about $7 for a 25kg bag. how much you add depends on the how much water is in the tank, can you take some photos of your setup, do you have aerators?

Aeration is from emptying of a flood and drain bed and water circulating from the tanks to the sump and some aeration from inflow to the four tanks. No aerating stones. System is about 600 gallons. I'll try to get some photos tomorrow, it's a bit late this evening to take them. I hope the fish can hold out until I get to town for the salt....

Yea I would look at putting at minimum 2.5kgs of salt in the tank you could even push it up as far as 10kgs, but It is probably a good Idea at this stage to add the 2.5kgs see how it goes and buy an aerator to help add more oxygen, I would recommend a electromagnetic one they are fairly efficient in regards to litres per hour to how much power they use.

Thanks!

It sounds like you need to cover your tank with some shade cloth. My guess is the fish were lacking oxygen and because they were gulping air near the surface got sunburned. It could also be that they have no plants or shade and the water is not sufficiently deep for them to avoid getting to much sun.



Got this from http://blog.thepondguy.com/2010/08/13/can-koi-get-sunburns-%e2%80%93-decorative-ponds-water-gardens-q-a-%e2%80%93-week-ending-august-14th/

This is for Koi but I suspect catfish would have a similar reaction.

I think sunburn is very plausible. I think the extra hot weather and too much sun caused a water quality problem and lack of oxygen and gasping at the surface caused sunburn.

Removed a total of 8 dead fish this morning.

I put shade cloth over the sunny side of the fish house. Tomorrow I'll try to get some salt and another pump or aerator. I'm guessing there are probably only a few live fish in the whole system. Even some of the Gambusia were dead yesterday. It's disheartening.

Here are some pics of the system:

tanks


flood and drain gravel bed


aeration in sump


the tank with the worst visible problems (seven dead fish)


beds of filter plants

My sympathies to you and your fishies. I know the feeling.

If you run a timer, turn it off and pump as much as you can.

If you are still feeding its worth not feeding for a few days.

It's also really worth getting a fresh water master test kit thinggy.

Just out of interest, what's the mesh around the tanks with duckweed for?

Have you got ducks you are trying to keep out?

Thank you, this is harder than I expected it to be. Found two more dead just this past hour; one of them apparently tried to swim up the SLO (I didn't know they could squeeze in there....)

The pump runs constantly, not on a timer. I've been feeding them minimally the whole time, live feed Red Wigglers and sowbugs/slaters, but I've not been able to tell if they were eating. Have not fed yesterday or today. Caterpillars and flying insects seem to have been fairly plentifully dropping in the tanks and my husband made a bug trap from a solar walk light to attract bugs into the water at night (it's in one of the Bluegill tanks).

The mesh was for the catfish jumping out when we first got them.

I am new to this also, and I lost almost all of my catfish last night. Might have a few left out of the 100 I had. But on a good note, so far the tilapia are doing fine.

Have you been able to figure out why they died?

My survivors are still looking horrible and I keep finding dead ones (total of 11 dead today).

hey

PM TC as she has lots of experience with catfish...

jT