Cheap Diy Aquarium Lids
 

I have several used 20 gallon long Aquariums that I didn't have any tops or glass lids for. Original I brought foam board and within 2 days it start growing black mold just I scrapped that idea ASAP. In a few of the aquariums I have some aggressive cichlids so I went to home depot to buy some egg crate lighting diffusers to make tank dividers. I came up with the idea of making lids for my tanks as well. On the inside I used layered aluminum duct tape. So far if been using them for about 2 weeks without any mold growth.

I used peg board for many years before going to a rack.