Rollitup

If you use dark nutrients or microbes they stain easy. Are you thinking root rot?

I hope not, got my water temps under 70F. but it always makes me nervous. The House and Garden Root Excelerator and Amino Treatment are both very dark so it could be that. Room temps are below 85 and air flow is great, 2 16 inch circulating fans in a 14x6.5 room and an 8 inch fan on the floor. The other thing making me nervous is my ph going up daily it seems.

Is it OK if there is a little water in the bottom of the buckets after watering? Could that be it?

Can you make a thread for this? It would be a lot easier to help you out. Hot reservoirs will raise pH as the heat goes up. Try to get your reservoir away from your grow. Are you using an ebb and flow with buckets? A little water in the buckets wont hurt, many designs leave a little.

Try to get your reservoir cooler, it might be best to back it off or put it by an a/c

Its good to have a drying of the roots, it fights disease and gives an explosion of growth, even quicker harvests. Getting too dry will kill roots off and slow uptake. You will need to find a happy medium. It might be best to ask in the hydroponics section. I use coco, its kind of hydro with a fail safe.