Cant get ambient temo up.

I just got my new Columbian RTB and I have him in a tub i cant remember the quarts off the top of my head I think it is a 31 quart. My hot side is at 90-91 and i cant get my cool side high enough. any solutions? its at like 76-78. Any suggestions to get it high enough. bigger peice of flexwatt? or what can I do, I have never had this problem before with any of my other snakes.

temps sound ok to me?

the cool side is ok then? i thought it had to be around 80 but if they sound ok the i wont worry about it. and humidity at 55 is ok correct?

78 is fine on the cool side for boas.

right on thanks.