i have a 55g tank and i want to house one or two crested geckos in it. i was thinking of making part of the tank under water, like a 18" section of the 48" length a fish tank with a little filter, some plants and fish. i would section it off with a piece of acrylic and use silicone to prevent water water from seeping into land part. i was thinking of something like this(of course there would be more plants in the tank)