Current Set up is a 38 gallon standard tank planted tank
Plants are a Ozelot Sword and Red Cryptocoryne that are both pretty good sized, also have a small pair of each Balansae Plant and Hygrophila (Temple Narrow Leaf)
Black sand substrate
Filers Aqueon QuietFlow 50 and Aqua Clear 50
Temp 77
PH 7.8
Ammonia, Nitrates, and Nitrites all 0 and under control
KH 5-6 degrees
GH 15-16 degrees

Water is tested weekly tank is about 4 months old.


I change 5 gallons of water out every week, use API stress coat to treat it.

Have a school of six cory cats that have been doing great since tank first cycled. I also have 5 tiger nertile snails, one of those did just die. Bigger is though is that I have tried to add a variety of other schooling community fish and they die over the first 72 hours. First tried 6 Serpae Tetras, they got popeye and were all dead in 72 hours. Then tried six green tiger barbs they all died in 48 hours. Thought it was maybe an oxygen problem so tried two female pearl gouramis since they can get oxygen at the surface as well. One was dead the first morning the other the next. The fish all seem normal and healthy during the day, but for everyone of them they are found dead when I get up in the morning. All were done at least a week apart.

I am pretty new to fish keeping has been years since I had a setup before this one. I don't think it is contaminates or the cory's would die too. The PH is probably a little high for the tetras that was my bad. Could it be that the water is to hard?

Don't really want to get any more fish until I find out what the problem is. Any idea would be helpful.

If I can't figure it out I may just add more cory's and just keep them in there.

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Joshua J Boehm