The 'tank Of Doom'

[mrlewis1978]

Hi guys

I currently have 4 tanks which I keep. These are a 2 foot, a 3 foot, a 4 foot tall, and 4 foot wide. I change the water every week, at least 20% in every tank. I use stresscoat plus to treat the water. Each tank has some easy to mantain plants, bogwood, a sand substrate, an airstone, and a filter which overfilters. If any fish show a sign of illness (which rarely happens in 3 of the tanks) for example redness or raggy fin, I treat using Melafix and Pimafix as per instructions.

Out of all these tanks above which I keep in the same exact way, I seem to always have dead/dying fish in one of the tanks. Problematically it is the largest 220 litre one. Which is fully cycled and hasbeen set up for 6 months. I was wondering if there could be underlying causes that would not show in water tests? I test the water every week which has completely safe results. I keep the temperature at 26. All of the fish in the tank are compatible in a community. Currently there are neon tetra, whiptail catfish, dwarf neon rainbowfish, a variety of corys, zebra loach, kuhli loach,a few otto and a few bristlenose plecs. This week I have had a dead false bandit cory, a dead kuhli loach, and a dead neon rainbowfish. This isnt unusual for the tank.

Basically what I am asking is if anyone has experienced similar, or if anyone knows of maybe diseases or viuruses which could not have obviosu signs or symptoms, survive pimafix/melafix and not show on water tests?

I am getting to the point of where I want to close the tank down, especially when all my other tanks are thriving.

Cheers.

 

[Dazzler666]

Hi there. Sorry to hear about your tank of doom!!! .
If everything is as you say & water stats are ok, etc is there any way to isolate some/all your fish from this into an isolation tank in order to see of it is actually a fish infection? Failing that & assuming your fish are ok I can only think that maybe your tank is contaminated with something. Have you used any aerosols, cleaning products, any of your cleaning equipment kept in the general household cleaning cupboard which could have become contaminated, etc?
All I can suggest is do several substantial (90%) water changes and see how it goes. If no joy then maybe consider disassbling the tank & thoroughly cleaning and re-start it.
Sorry I can't be of more help & do hope you find the problem!!

 

[mrlewis1978]

Thanks Dazzler. Something contaminating the tank isn't something I had considered although makes perfect sense. Although I have never cleaned the tank with any products it was from eBay so the previous owner might have. Could it still be effecting the tank after being set up for 7 months?

 

[Dazzler666]

One thing ive found with fishkeeping is sometimes the inexplicable is the cause!!! Cost me quite a few fish to find that out too!!! Lol.
If your tank of doom has always been like this then yes i would say its quite plausable as its quite easy so far as im aware that possibly toxic residue will remain then just infect your substrate & so on hence, vicious cycle begins!!
Ive also been told simple things like air freshener, polish, etc can pollute a fish tank & wipe out all the fish!!
Gives is all something to think about .... Who said fish keeping was easy!!!! Lol. Well, i thought it would be and guess what .... I was wrong!!! That aside, once i got into i love it hence why i now have four tanks, one being five foot which is my new addition & pride & joy!!
Fingers crossed anyway you get to the bottom of it ... As so to speak!!!

 

[CezzaXV]

What exactly are your readings? Not doubting that they're fine, but we get a lot of fishkeepers around here having problems who insist their levels are "fine" but when questioned on it, it turns out they're actually far from fine.

26 is a little high for most community tanks. I'd drop the temperature to 24 if I were you.

Possibly worth doing bigger water changes on that tank, as nasties might be building up in the tank faster than you're removing them.

 

[PrairieSunflower]

I had a tank of death and I removed all the ornaments and it miraculously was fixed.

Some other ideas... how about water circulation? Sometimes if you have pockets that are quiet with no water circulation then it can have pockets where the readings differ. I know my fish like to sleep in the quieter places but I try to keep plants trimmed and make sure that the water still circulates in those areas.

 

[Tolak]

I had a tank of death and I removed all the ornaments and it miraculously was fixed.

^ That. ^ Eliminate variables.