The smaller fish in the tank can use it to hide in, i was originally going to add a lot of RCS and the purpose of the rocks were for them to hide in. Now it just covers up the ugly looking sponge filter.
From aussieJJDude on 07/05/12
love the rock pile. can they swim though it or is it a 'waste' of space?
Tyyrlym's 10 gallon freshwater fish tank, Quarantine