While I was looking for information on caring for Fiddler Crabs, I came across a post about building a hill and waterfall in an aquarium for Fiddler's. I thought about this for a little, and came up with this idea.
It occurred to me that building a hill high enough to reach above the surface of the water would result in a lot of wasted space in the aquarium. I decided that this space could be better used if a hollow block was used, with gravel glued on to create the hill. This hollow block would have one open side that would be placed flush with the side of the aquarium.
filter would be positioned so that the siphon tube would extend inside the hollow block, and the overflow would spill onto the hill and create the waterfall.
Inside the hollow block I would place some plants. A light would be positioned on the side of the aquarium to keep the plants healthy. The hill itself is angled at the corners. Intake holes would be positioned on these angled corners to allow water to flow in, but minimize the light spillover.
It occurred to me that if I were to paint the side of the tank that the light was on with a non-reflective or light absorbing (if I can get any) paint and leave only a clear patch to view into the hollow block, then I could minimize light spillover. Without light spillover, I believe that I could leave the light on 24/7 without stressing fish or crabs. Is this correct, or am I overlooking something?
If I do leave the light on 24/7, then I would size the intake holes to allow shrimp and snails to pass through, but not crabs or fish. I hope that the shrimp and snails would be able to handle the algae growth that I would experience within the hollow block from the 24/7 light source.
I have attached a crude picture of what I'm attempting to do.
Would leaving the light on 24/7 be feasible with this setup? Would the entire setup work, or is there something that I'm overlooking? What are your opinions about this?
Thank you for your time.