You actually are going to need a submersible cooler for your reservoir.
the colder the water, the more aerated it can be.
its a good idea to cool your reservoir.
This is actually totally wrong!
For rooting cuttings its all about water temps 76 degree's is perfect I also like to keep the air temp cooler like 70 and just use some crapy clf!
For growing yes cool water 68 but roots thrive at 76 that is the secret to getting roots in 5 to 8 days!!!