Everything has gone to hell since my last post. Please help.

Dont waste money on RO water or a filter. Doubt your tap water is in that bad of shape. I wouldn't waste any more money on these plants, just let them grow out using what you have. You're going to get what you get from them at this point. Dont chase bad money with good money as they say.

Is there a reason you chose coco over soil? If you dont have a good reason, switch to soil for your next grow. Dont have to worry about PH and all this other bullshit you're dealing with. Ditch the GH nutrients and pick up something like jacks classic or dynagro lines.

Im not against ro but if you have a dozen or so plants its really inconvenient unless
you get a system.

Ok guys, thanks a lot for the advice. I hate giving up on things, so I'm going to try some of these tips and see if I can save these plants. I'll learn as much as I can from this grow and definitely move on to soil for the next one.

No expert here, but had a plant do this last yr. started getting mold too. Lucky for me it was the last week, when I dumped the soil, the bottom had ice on it, the room was kept at around 80 degrees. But the room under it was unheated all winter, In turn floor was cold enough to freeze soil. They always say look at roots to find problems, good luck