I'm in the process of cycling a 10 gallon tank to eventually put a couple bettas in(with divider obviously). I haven't been using a filter for the cycle, but I just found one around my house that was used in my old saltwater aquarium. I'm wondering if I clean the filter up well enough, is it ok to use in the betta aquarium? Or is there something in saltwater tanks that can be harmful to bettas?
There are a some particles/saltwater organisms that are stuck to the filter and are a little hard to remove. I forgot what they're called, but they are very common and completely unharmful in saltwater tanks. Just not sure if they're ok to be attached to the filter in a betta tank. Regardless of what they are, they're are definitely not living.
Why do you think?