I'm not too excited about Goldies/carp .... they're pretty susceptible to just about everything that comes by ........... I killed about 45 or so just trying to get started ..... now I use cheapie feeder Guppies (10-20 cents each) to get my system cycled and haven't lost a one yet ..... plus when you stock it with Tilapia or another larger fish, they become food for the new fish ....... Tilapia love Guppies, but carp/Goldies don't seem to entice them that much for food .

Temps should be well into the 70s-F and preferably the '80s-F if you're going to go with Tilapia, and the Guppies are fine with those temps. Like Oliver has said, we need more readings than the PH ..... my local water is 8.4 and it won't be brought down no matter how much I try, so that reading could be your local water that just can't be adjusted ..... we gotta know more ........