I just mounted my light by hanging it from the ceiling. I tried my best to cover the tank but when I was drilling the ceiling a bit of paint residue got into the water. Do you guys think this will effect the fish at all? I mean if a little paint can harm humans what would that it do to fishes. Hope nothing goes bad by tomorrow morning.

did you take it out? did the fish eat it? are you still using lead paint in your home?

nothing should be wrong as long as you took it out.

You did net it all out didn't you? Paint can't be good, but if you got it all out I would think things should be alright considering the paint etc was all dry and cured. I believe if the fish got a taste of it they would just spit it back out.

got most of it out but there is still some residue in it. I saw a few fish try to eat it but they spit it right out. I'm just worry about the paint when it starts to liquify and goes all over the water.

if it's dried, it's mostly fine.
The toxic medium is cured when it's dried. Depending on the color of the paint, the toxic pigment varies. If it's white (titanium oxide, zinc oxide), you're fine. maybe. It'll kill any inverts before the fishes.

If it's a newer paint, it's likely latex (especially on the ceiling of anything but a "damp room" like a kitchen or bath) which once it's dried is basically colored plastic. The ceiling itself is (probably) drywall which is basically gypsum (CaSO4·2H2O) which has a lot of uses, one of which is as a soil conditioner. If I remember correctly it's supposed to improve the structure of hard clay soils. An older (1970's or prior) "popcorn" ceiling may have asbestos in it, but the fibers have to be inhaled into lungs over a period of time to be dangerous. I wouldn't worry about it. Like mistergreen mentioned, if your shrimp/snails start dying (assuming you have any) then you know you've got a problem.

Haha I have too much Malaysian snails, this might be a blessing in the long run...kidding. Well this morning all the fish seemed to be ok. Thanks guys.