Fish dying within 2 hrs in tank

**Liannnnnnnnnn** · 11th Jul 2016, 23:07

Hi all,
I've been introducing yamatos and cardinals to my tank but every time they wipe up within hours. Below are my specs.

Tank has been up and running for 2 months, fully cycled with 0 ammonia, nitrates and nitrites. CO2 at 0.5bps. Plants include monte carlo, rotala wallichi, pogostemon helferi, staurogyne repens, alternanthera reineckii, zenkeri. Fresh new ADA substrate. Eheim 2215 with CO2 reactor.

I find it difficult to narrow down on the causes of death as my other tanks are run with almost identical set ups with zero issues. Fauna are all acclimatised gradually prior to introduction to tank. I dont think its a weak batch of fauna that I bought since it has happened 4 times already... they die all over the tank, with some bodies found at filter inlets. I suspect it is copper poisoning because whatever is killing them it seems to be pretty potent. But i've done heavy water changes every few days to dilute whatever remnant copper would remain. Can someone help solve my mystery?

**milk_vanilla** · 12th Jul 2016, 08:24

Hi,

How big is your tank? What kind of ferts do you use ? How is your dose ? Did your use anti cholrine during water change ? Are you using tap water or other water ?Did you use other water conditioner ? Did you use excel /other glutaraldehyde products?

Sorry we try to help but may need more. Info's

**Liannnnnnnnnn** · 12th Jul 2016, 09:36

It is 1.5ft crystal tank. Currently havent begun any ferts regime as the soil still fresh. Occasionally will add a bit of seachem K. All tap water is dechlorinated during water changes. I dont use excel, only pressurized co2. Thanks!! Pls ask more!!

**Urban Aquaria** · 12th Jul 2016, 13:29

Did you track your tank water Co2 levels with a drop checker? And the indicator color maintains at the safe green color range?

**Liannnnnnnnnn** · 12th Jul 2016, 15:39

I used a drop checker initially, but after the co2 stabilised at safe green i removed the checker. It is currently running at 0.5bps and I havent increased it since set up. So far plants are happy and pearling under the GE evo light.

**Urban Aquaria** · 12th Jul 2016, 15:45

Originally Posted by Liannnnnnnnnn

I used a drop checker initially, but after the co2 stabilised at safe green i removed the checker. It is currently running at 0.5bps and I havent increased it since set up. So far plants are happy and pearling under the GE evo light.

Maybe it would be a good idea to install the drop checker back again, at least just to make sure that Co2 concentrations are still at safe level... there are possibilities that Co2 could slowly accumulate over a period of weeks or months into toxic levels.

Also make sure, if required, to use 4dkh water to mix with indicator reagent (not aquarium water) or use pre-mixed indicator solution, to ensure correct Co2 level measurement results.

**AQMS** · 12th Jul 2016, 16:38

Do you have any other fauna in the tank?

**plantedpot** · 14th Jul 2016, 16:39

i had the same problem for one of the tanks which i setup using bottom sand. Water was crystal clear, and plants were doing well as I used based ferts and root tabs.

Traced it down to eventually silicate and dissolved solids. Never really did a detailed investigation, but i suspected the water had too much dissolved solids which prevented oxygenation. For me, the fishes gasping for breath was a tell-tale sign, though water was crystal clear. Eventually, I resetted the tank and used Advance Soil as substrate. No problems ever since.