Dwc/bubbleponics water temps

So I'm somewhat curious, I know alot of people are using are using frozen bottles of water, is temperature consistency important? Can I make the water too cold? Does the temperature requirement Change with the different stages of the Plants life Cycle?

Consistancy i very important in growing indoors but the frozen water bottles do work fine. the key is to break the hot cycle so as not to have rot problems. Below 64 is not the best but still no problems ive seen when using tap water that is in mid 40s in winter. Temps do not change with stages.

I never worried about my rez temps til recently when I discovered algea growing on my airtubes. Bottles of frozen water don't fit in my rez very well either due to the large root balls that have taken over...I'm afraid a frozen bottle might slide over & cover up the airstone bubbles thereby drowning my girls as they are almost finished. I started filling up ziplock freezer bags with water & freezing them flat. This seems to help keep the funk away along with adding h2o2 every other day...ph has remained normal for a couple weeks now.