when i got home today, my power in my house was off. a transformer had blown down the street. i have no idea how long it was out for, cause i was at work for about 4 hours. i tested the water, so far its all ok (no ammonia, nitrite, or nitrate)- but i did a water change and did not feed the fish their second feeding, just to make sure that if the electricity in my filters was off long enough to cause a mini-cycle in my tanks, that they would have a chance. my question is; how often do i need to check the water, to see if the bacterial load has been compromised?? if i lost some of my bacteria, when would it start affecting my fish?? so far everyone is ok.