Just looking for some info on why my ph drops, drops from 8.3 to 8 in roughly a day and a half, bring it back up and back down it goes. Tank has been going for about 2 months, fish are doing great, did a few water changes already, all readings on the test kit are 0 (ammonia,nitrite,nitrate) only had a skimmer going for about a week and a half. the water I use has a ph of about 8.3. any thoughts ? plus I am using a marineland hob 400 filter and 2 power heads, one 1050, and a 530 on a 50g tank.