If there were a risk it would probably be colour dependant for example green or blue paint may comprise a pigment from either a copper, chrome, cobalt or nickel source depending on the shade. Safe colours possibly could be black paint (carbon black) or white (titanium oxide). Acrylics are pretty inert when fully cured so they shouldn't leach anything into the water however something mechanically browsing that surface may ingest small amounts of it, I doubt a copper based acrylic pigment that had inadvertent edibility would be good in an invert tank. If I were in doubt I would add a clear coat on top just to be sure.
Hi, I would be wary of using a solvent based paint without drying at high temperatures and leaching in water many times before use.
Looking at the msds it contains quite a number of high boiling solvents like xylene which could leach out if not fully evaporated before immersion.
I wouldn't use water based paint either for whatever you are planning as they will contain isothiazolones as preservatives which are highly toxic to aquatic organisms.
My personal opinion based on years of working with these products.