I have had this fish tank for over 5 months and everything was fine until all the fish started dying. I have not made any changes to it lately and I’m intrigued as to what might be causing this disaster. I change 20% of the water every week and my water params are Ammonia 0, Nitrites 0 and nitrate 20 ppm. The fish just die, some without any previous signs and others seem like they want to get out of the tank the day before.
I sometimes siphon the water to my sump and I can feel the water has a burning sensation, something like maybe Wasabi (the green sushi stuff). I have posted a previous question but did not include the water burning sensation. I of course treat my water with API Water Conditioner so it must not be chlorine or chloramines. I have seen some of my Cherry Shrimp around lately and the rest of the fish seem fine but today 1 more died, a very hardy baby Swordtail that was born in the tank like 2 months ago with many others and they are all fine. Any help will be greatly appreciated, thanks.
pH is 7.4, temp is 74-76 F, GH-KH=?. I have not added plants or gravel lately but I did add a couple of Blue RAMS that all died. It is a 55 gal tank with a 20 gal sump. I have a total of 2 adult Swordtails, 1 Synodontis catfish, 4 Serpae tetra, 4 Neon Tetra, 1 Siamese algae eater and like 15 baby swordtails, oh and 10 Cherry Red Shrimp. There are no toxins sprayed around the tank, I have no other pets.
I did dechlorinate the water with API Tap Water Conditioner, I do not use any chemicals around the fish tanks.
