Your tank is set up already? In the house? With fish in? If so oil based paint is gonna stink BUT may be safer in the long run. Sorry I didn't read the whole thread. You don't wanna spray in the house your gonna get ALOT of over spray TRUST ME, I did it and had paint everywhere. I covered everything too! And the vapors lingered for a while.
So roll on, if your tank is in the house and set up might me a safer route. If not and it where me is spray away.
"When creating an aqua scape, strive for the beauty of imperfection, as its art and there is no wrong or right, it's left open for interpretation" James Findley