So dont glue the rocks down to each other also how many yellow labs in a 75 gallon can i fit and would 2 aqua clear 110 be enough filteringIt depends on the shape of the rocks. I would avoid doing that, because no Malawi tank set up is permanent. You will find you have to move things regularly, to get debris out and to adjust as set ups need to be improved. No one gets it right the first time, and even if you can, the fish will force changes.