what is the ideal ph and temp?

It depends.

Most pHs are mostly OK most of the time, although sometimes you may want to be in a particular range for a particular reason.

Likewise the temps, although most tropicals do best in the upper 70s. I keep my temperature around 78 or so and my pH is around 6.5.
 
I think what's 'ideal' depends on what you're keeping in the tank. Most 'community' fish are adaptable, and don't need a specific pH to be happy.
I use CO2 in my planted tanks, which keeps my 65g at 6.6, and my 10g at 6.8-7.0. The temperature in both tanks is 79-80F.
 
IMHO, the best PH is what your tap water is......
and mine is 8.0-8.2!
Unless your trying to breed certain fish, then, and only then, would I play with it, and that would be by lowering/raising the KH by using RO(to lower), or buffers(to raise).

As far as temp., depends on the fish. One tank is at 74, one is at 80, and one is at 76.
 
White cloud minnows and cories stay at a happy 70F. Super active and very colourful and lots of egg laying. PH is 7.4.
 
AquariaCentral.com