If you have algi then light is getting into your system. Water temperature is a point of debate with a lot of people. Cooler water can hold more oxygen the warm water so cool water is preferred. BUT...................................

Clones like a warmer temperature (the root zone likes 80f and the tops 85f). They get their oxygen from the air gap between the stem and the water line.
The next school of thought of many is the root zone temperature should be 5-8 deg less then the air temperature to stimulate roots.

The temperature I use is 5-8 deg F less then the air temperature of the clones. I have found that produces the best results for root growth. Less stress on the plant is what I believe is key to happy healthy grow and that is a good thing.

Anti-Wilt is a must in my book if you want to grow from clones with any success.