1-year maint.


My 75 gallon plant tank is doing well a year after being setup.  The 
substrate is gravel with laterite and heating cables.  I vacuum the
top layer of gravel at each water change.  Do people recommend a really
thorough deep vacuuming of the gravel, i.e. deep enough to disturb the laterite?Is this recommended only if algae problems get bad?  Does the fish waste
get broken down effectively in the gravel (the fish load is medium)?