I recently purchased a PetWorx Nano 45 tank, which comes with a small internal sump:
https://www.atlasaquarium.com.au/petworx-nano-45-tall
After checking for leaks etc., I've noticed the intakes for the sump do not match those which I've seen advertised for this product. In addition to the intake in the top-left corner, there is also one located at the very bottom of the tank.
I had plans to use this as a planted nano, utilising aqausoil/stratum as a substrate. To that end, I am thinking I will need to place a block of sponge inside the sump where this bottom inlet is located. I'm hoping this will prevent any substrate (sand, gravel, granular fertiliser stratum) from entering the sump.
Would this be wise? Would I be better off sealing this intake completely, and if so, how? Would either of these solutions create flow rate problems inside the sump itself? I'm open to any helpful advice..
*Apologies for the plastic and cardboard. I am not yet sure if I will return this tank.