I did use a smaller air pump and having issues keeping my temp at 76-78f.
Can’t get it below 80f. I even dropped the temp in the room to 75f. I would imagine it’s the pump causing the rise in water temp?
The pump, light, ambient temp, and how insulated or heat conductive the surface the cloner sits on all can impact the water temps. What are the temps in your aero system? My aero cloner ranges from mid 70's to mid 80's, its usually about the same as the ambient temp in my grow tent, I think the concrete floor under the tent offsets the heat created by water pump. I haven't had any issues getting clones to root in that temp range but I do change the water more often if its hotter and the cloner is always sterile.
Based on the pic of your setup one thing you could do that might lower the temp would be to put your air pump under the cloner. It looks like you have the cloner and pump up on some kind of shelf or cabinet, with the pump directly under the light sucking up warm air, if you can put the pump underneath in the shade where the air is a little cooler that could shave off a degree or two.