Re: the hollow decoration, I've got a sort of buddha statue that has no access to the inside but the bottom which is planted firmly to the substrate. Is there a way for me to seal off the bottom since u said stagnant water can cause issues? there is no way for the fish to get in, only water
That’s exactly the kind of decoration that can cause issues as far as I know. I think you can seal it, yes. Aquarium sealant should work, not sure about the best way to go about it. Maybe fill it up entirely, or glue something to the bottom to close it off?
Anyone have experience with this kind of thing?