Hate to give ya crap about this, but 2 is not enough, and a 29gal is far from adaquate. The temp honestly wouldn't concern me too much, they get those types of temps in the wild. Bouncing the water temp up and down with ice and such is only gonna cause them stress. Being that warm though will increase their aggression levels, but they should be fine. Just keep an eye on them, and increase the airation in the tank, higher temps mean less O2 saturated in the water.