Hi to all you knowledgeable ladies.
My cardinal tetras have got what look like tiny air bubbles on them. They seem otherwise happy and no obvious change in behaviour. My water parameters are all fine. Could this be ich? We've not added any new fish for about 4 weeks so can't understand how it can be. Could they be tiny air bubbles from brushing through plants? Want to get on top of treatment if it's needed before it spreads to other species, but having read about it, don't want to medicate if unnecessary.
How do I know for sure either way? We've been so fortunate so far, don't want it to go horribly wrong now. :(