internal parasites?

I’ve been doing a fishless cycle for about a month and a half and I finally got three new mollies in the 20gallon tank! When I first put them in the tank ammonia was 0 the next day but I had nitrites fluctuating between 0.25 and 0.5. I did a big water change two days in a row and skipped a day...

I have a 20 gal tank with wcmm and just decided to add guppies. The place i got them from was like a mom and pops fish store so I thought it would be okay to just add them in. Now that ive been looking more at the females I noticed some have this sting coming out of them but only them and I know...

Hello I am fairly new to this forum, I am now a owner of four male guppies. They live in a 6.7 gallon tank and unfortunately I feel like it’s my fault for not noticing that when I brought my three new fish to add to the tank one of them was acting odd. I’m talking about swimming by the filter...