well i just got back from vacation a few days ago but then had foot surgery so i could not do my weekly water change. i tested my water before the WC and the readings were pH-6.2(low) ammonia-.5 (high) nitrite-0(good) nitrate-10(good). so i did a 50% WC and went out for the night. when i came back my water is yellowish/gold. i did add baking powder for a quick fix for the low pH levels. so i retested my water with all the same results again. fish are acting fine. eating fine. no problems. i do have some pieces of driftwood but they have been in there for over 6 months now. i am thinking that one filter shut down during WC and when i got it up and running a lot of junk came back in the tank. i really dont know. any help or advice? thanks guys