1. Which is a better tank regardless of price, a 40L or a 55? They have the same surface area so if all else is equal, are those 15 gallons really beneficial to add to parameter stability, gas exchange, stocking, etc.?
2. Have come into an offer for a Fluval canister that is almost too good to pass up, but I already run a really efficient wet/dry sump. Has anyone experimented with running a canister sucking water out of the resivoir of a sump and returning it back to the sump? I do not want to run it inline with the return pump/uv sterilizer because I don't want to deal with matching gph flow.