Backyard Aquaponics
A place to discuss aquaponics

I've just found a Catfish fingerling floating and checked my water quality.

pH: 7.6 (normal reading)
Ammonia: 0 (normal reading)
Nitrites: 0 (normal reading)
Nitrate: 0 (normal reading)

Fish Tank Temperature: 24.3 degrees Celsius
Air Temperature: 35 degrees Celsius
Time of day: Noon

Water was salted to 1ppt prior to adding fingerlings before Christmas.

There's a red patch around the fish's anal area? and are those small white dots Ich?

Should I now salt up to 3ppt?

Thanks in advance for any help.

Looks like something's been eating his tail as well. What else is in there?

Salt now would be my first action. It's not the temp - been much hotter in the water here and my cats are hitting the food and competing with the SP's for it.

Don't know about the red patch symptom...

Be careful with salt, scaleless fish dont cope with it too well. Someone with more experience with cats may be able to give you tolerance levels.

Thanks Guys.

Journeyman:

There's only 29 Silver Perch and now 3 Tandus Catfish in the tank and they're all around the same size.


Charlie:

I'll wait an see if someone with the knowledge lets me know on how much to salt up with Catfish, the water was salted to 1ppt when they were put in would that have caused any problems to the catfish?


It's very hard to see and problems when they all stay close to the bottom of the tank, it's not until you get a floater do know there's a problem.

How long can I leave them unsalted before I get more fish dying?


Thanks again for your help Guys

Have salted my big system to 6ppt when I had catfish with red blotches and it fixed them up. These were two year old catfish

Hi Mantis:

From the photo do you think the red blotch was the cause of death? or was it Ich? and do you think salting would harm smaller fingerlings?

I have small cats and they are in about 2ppt so I know thats ok, I read somewhere on the forum that fingerlings have a salinity threshold but I cant find it. I dont think the salt is the cause in your case, possibly started with ich which then caused the red blotch etc

Thanks Charlie I'll salt up to 2ppt immediately and take it from there.

3ppt seems fine as well - mine have been at that level for maybe 4 months or so - since I lost a couple of SP's. I check it about once a months and I've had to top it up once to get it back to 3ppt. It might not evaporate but the GB seems to absorb some I think.

I haven't lost any cats and they are growing about the same rate as the SP's (or maybe a bit faster - they started a month behind the SP's) so it seems a healthy environment for them.

Thanks Journeyman

Hi Joblow

Your fish looks like it has been dead for a long period of time???
The value of salting is achieved by suddenly bringing it to 3ppt - shock value. That is what I was advised when I lost a Catfish early on in my AP system. "Tonic value" when you continue to run AP system at 1.5ppt. (Salt helps with fish slime coat).

Pic is of my first casualty back in 2009.

Best wishes - ColinW

Hi Colin,

I have just picked up the salt and not put it in as yet and will take your advice and only salt to 1.5ppt and see how that goes for now and add more salt later if needed.

You're right about it about it being dead for sometime, he may have been caught under the SLO and just surfaced and that could of even been his fate, but the white specks lean toward Ich but that might not have been what he died from.

Thanks for the advise.

Hi Joblow - I would do the salt 3ppt now!!! Leave it at 3ppt for 4 or 5 days - then slowly bring it back to 1.5ppt for a couple of months. BUT that is me. Best wishes - ColinW

How do I bring it back down to 1.5ppt? Just a water change?

Just add a bucket or two of fresh water every day until it drops. Some of your plants will uptake some salt - some should come out your overflow as you add fresh water. (That is how I manage salt). Best wishes - ColinW