Haslouer
Aquarium Advice Newbie
For 4 months I"ve been trying to establish a smaller tank (20g) with some basic fish - 1 good size pleco, 1 gourami, 2 high finned tettras. It was an old tank that had a goldfish in it. Removed goldfish (donated it to someone), stirred gravel, removed most water, replaced water with tap. The fish I put in are doing ok, but I when I add new basic fish - a few tetras and platies they did not make it. The panda mollie I added with the others is doing fine (but it's a pig eater). Nitrites/nitrates & temp ok. Ph high - even when treated. What could I be doing wrong?