HCA: Hermit Crab Association

Good afternoon. How long does it normally take to increase the temperature in a tank? I just learned that I need to have my tank between 80-85. My tank was normally between 73-75. It's now up to 79 degrees I have two ZooMed heaters on it one for a 50-60 gallon on the back and one for a 40gal on the side. I've also wrapped the back and side with a reflective visor. I'm just worried if it's enough, if it's not enough, what should be my plan of attack if it doesn't work and how long will it take to find out.
Thanks in advance for any advice.
Sorry I have a 40 gallon tank currently heat is at 79 humidity 75

If you have PPs, over 72 is a safe temp. They do tend to be a bit more active if it is closer to 80. So your 79 is great.
Check to be sure that your type of UTH can be safely insulated over top - do you know the brand? Or where you bought it? For the UTH's, we go by dimensions rather than the number of gallons listed on it (the gallons measure is for reptiles, where they use the UTH differently).