New Axies, tank suggestions? General Questions

So as of right now, this is my tank set up for both tanks:

Fine grain black aquarium sand
Large hide
Plant decoration (live plant coming soon)
Bubble stone
Sponge filter (possibly will be taking out and turning normal filter back on, it seems useless)
Normal filter with slowed flow
Thermometer
Fans on the way.

Any opinions? This is my first time, so I'm sure there is room for improvement. I am having trouble keeping the water temp down, right now it is at 66-68* F, any suggestions about keeping it cool until my fans get here?

I also just changed their water 20% and treated it for ammonia, as the level was a little more than zero.

Also, they each get a 1/4 to a 1/2 a cube of blood worms twice a day. Am I feeding them enough, am I feeding them too much? Can I switch them to something else or should I keep them on the bloodworms until they're bigger? They're probably around 3, maybe 4 inches long right now.

Thanks in advance!

To keep the temp down I'd turn the AC on in the room if there is one. If not put up normal bigger fans in the room to keep it cool.

I'd feed them 1/2 a cube of blood worms each and I'd only feed them once a day. When they get to about 6-7 inches you can feed them every other day. When I feed mine everyday he won't eat it.

I'd suggest mixing up the food. Like also feeding them frozen (or live) brine shrimp and even frozen beef heart cubes you can get at the pet store. I personally feed mine blood worms one day, brine shrimp the next, and beef heart last.

Anotherway to supply your food is you could do is a brine shrimp farm. I had one going for a while and it's VERY simple, easy, and takes up like no room at all. Here is a link to how to build one if your up for doing it:

https://www.youtube.com/watch?v=6ExC4-k5oxk