been feeding plants with 39f water

My plants look kinda fluffy during flowering, I'm supposed to have about 1 week left but they look like they need 3 more weeks. Could it be caused by super cold water? It's very cold but the water quickly heats up when it hits the coco which should be at room temp (+-79f) right? Anyway I just bought water heaters to set th temp at 73f. Anyway I'd like your thoughts on ice cold water. Btw yes those are spider webs, we don't need to talk about those

Can't remember where I read it so hopefully someone else will chime in but I'm pretty sure really cold water fucks up the roots and causes nute lockout and slow growth. Could be why they look they way they do.

I don't see spider webs