Aquatop Canister Filter with UV, heating up water?

Been a while!

I've set up an Aquatop canister filter for my lotls, plus their offspring that live with my parents.

The same time correlates to a bit of a heat wave, but we A/C our homes, and I've never really had temps go above 72F before with the overhang filters. However, since setting up the canister filters, I've experiences some crazy spikes, at my home to 74F, and at my moms to 76F which required about 30lbs of ice to chill and stabalize.

I thought it was the UV lamp, so I turned those off. But it seems that they creep to 72F anyway...

No direct sunlight, homes are kept below those temps...any experiences/thoughts?

Canister filters have stronger pumps, stronger pumps create more heat.

Something else to consider is the output. A hang on back creates a lot of surface disruption which causes a lot of evaporation, which cools the tank considerably. What is your output like for this? Above water? Below water? Simple tube, spray bar, etc? That could be a big reason.

Now if you really want to get funky and create a much better living arrangement for your axolotls you can buy a mini-fridge off of craigslist for like $30, drill two holes side by side in the wall and buy a really long tubing in the same size that your canister filter is already using, you run the output into one of the holes, put the majority of the really long tubing coiled up in the fridge and then run it through the other hole and up to the tank. Run a bead of silicone around the holes to seal the cold fridge air in, shut the fridge door and turn it on. This way your water will go through your canister filter, get filtered, go out and run through the tubing in the fridge before re-entering your tank.