Quote:
Originally Posted by sasquatch  is the gravel set up as an undergravel filter? if it is changing it all at once will create a problem |
the gravel is on the bottom and the water goes through slats on the bottom which gets pumped up to the top which THEN goes through the filter medium....the filter is on top, gravel on bottom, so then it shouldnt be a problem, right?
or just in case should i throw a pack of biospira in when i change the gravel?