New to PacMans.

[DVirginiana]

I assume you're talking about water dechlorinator. I own several Bettas and if that's what I need will water conditioner for fish work? And if you're wondering its not the "stress coat" that helps the natural slime coat for fish. It's just standard water conditioner.

I use Prime for my reptiles and fish. Works great. Most water conditioners have deaminator and dechlorinator in them, but check to see it has both to make sure. Yeah, you need to change out the substrate asap. A day or so in it probably hasn't hurt him, but if you leave it he will tox out.

Britta filters don't remove any chemicals. They only remove organic material like bacteria.