Are clear coats waterproof?

A friend of mine is working on a plane model which he wishes to display permanently or temporarely (don't know which) underwater in an aquarium. I don't know if the whole plane or just part of it will be in the water. I didn't asked. He will coat it with clear flat to dull the paint job and protect the decals. Will the clear hold underwater and for how long? Also will the water be safe for any fish he might leave in the aquarium where the plane will be displayed. And finally which flat clear would you recommend.

Thanks in advance

It will be waterproof for the decals, but it won'T stop water to enter in the model.

As for the fish, if the clear is fully cured, I don't see why it would be dangerous.

it would definately have to be weighted. for it to sink. unless he wanted to allow the fusalage to be filled with water. that would probably be the best thing to do. clear EVERYTHING. that way the water didn't degrade the work over time. and then allow water to fill the whole fusalage, including the cockpit, just my .02

I don't see how it would be a bad thing. Mostly clear on the decals so they don't come off, everything else should be okay. Water does eat away at everything, but it takes a REALLY REALLY REALLY long time. Can't see it hurting the fish either, just make sure he gives the clear about 10 days to harden and fully cure

I'd also suggest not using water based acrylics, because they would probably be more likely to get soft or dissolve into the water after long amounts of time.

I would suggest using a flat lacquer as a final coat.Maybe even wait until the tamiya flat spray is available as it will be good for sure.

I would test it in a friend's aquarium first to see if the paint kills the fish. plus the glue, and plastic itself.

plastic is a PETROLIUM product!!!! (made from crude oil byproducts) so use caution!!!! as for sealing the decals, I would use laquer only, as enamels take such a long time to gas out, and acrylics are a water based paint anyway (that's a no-brainer)

should make for a really interesting aquarium display.

The tires would start to decompose after a year or so
Update NEVERMIND! i saw that you were talking about a plane now and not a car :P

I have a Minicraft submarine model in one of my tanks, freshwater, been there about 12-15 years. It has weathered nicely. A couple fights with an angry Oscar (the fish started it) and some of the paint, both lacquer and enamels, got scraped off, but that didn't kill the fish. Even the Plecostomus works at cleaning it but most of the paint is still there. Between them they pretty much wiped out all of the rigging and railings, the decals were gone in less than two years... - Mark
http://i2.photobucket.com/albums/y1/DoctorJones/DSC09520.jpg