I recently setup a small (10 gal) aquarium. It was cycled, so I added some endlers and about 5 red cherry shrimp from an established tank. Soon after, I purchased another endler from the local fish store. Though apparently fine on arrival, he soon began to grow emaciated, refused food, and died. The other fish in the tank also began to hollow and lose their color, and then the RCS began to die every few days. Water parameters are good: 0 Ammonia ) 0 Nitrite 5 Nitrate. Temp is 78 degrees. On recommendation, I first dosed the tank with Metro and Focus for 5 days. No improvement was apparent, so I started a regimen of PraziPro. One fish seems to have partially recovered (he swims around and seems happy), but he is still not eating. The only other surviver often floats at the top of the tank. One interesting thing to note is that, when these fish died, most of them died with their noses down and their tails up. If all is lost, then I'm thinking of removing the substrate and starting the tank over with only RCS. I'd like to keep my rocks and filter media so the tank doesn't have to cycle again, but do you think the internal parasites from the fish would infect the RCS? If so, does anyone have an idea about how long it would take before the parasites die without a host? Thank you for your help.