well, i am guessing that you have the lights on most of the time.....am i right? they will feel much more secure and likely to venture around the tank with the lights off. well thats what my fish taught me anyway. as Dino stated cover will help as well. my RBPs had the tendency to destroy fake plants, and i would recomend a submerged shelf over a small portion of the tank like around 1/4 of the tank and about halfway down. this gives them a good place to hide when they get spooked. also you want to keep the tank in a low traffic area. hallways and next to chairs or anywhere you go frequently is not the best place for a RBP tank. they will flip out all the time. the only time i turn on the light is for tank cleaning. i have had my fish for several years and when that light comes on they scoot to the other side of the tank, i do my thing and turn the other hood light on and shut the first one off, they swich sides, and i finish the other side of the tank. i haven't had a fright response during gravel vacuming in some time. also, you need at least a 55 gal for 3 RBPs. when they get full grown it will get crowded in there and if you don't plan to upgrade you may lose one to stunting or aggression from the other fish. just try to be patient, it was at least 4-5 months before i ever saw my fish eat.