just chiming in, looks like i spoke too soon. the chlorinated water does seem to be helping. now that i'm only using chlorinated water only a very small percentage have the reddish roots.

How do you treat your plants? Did you use a fungicid? I used activated charcoal in non chlorinated water and it worked (no red traces for 2 weeks) but then I changed methods. :(
Each experiment is a learning lesson I guess.

I've seen that happen in my floated seeds too. I used some hydrogen peroxide in well-water, but nothing else.

I don't think I was changing the water daily on some batches.

Will they "recover" or you think they will develop the disease and eventually die?

So your advice is to change back to 1.5% h2o2?

I really didn't pay it that much attention at the time. I thought the tiny red tip on the root was normal (and it might be) so I planted those anyway. It was red in the very tip of the root and not a very bright red like in a stag infection.

I thought the red on the sides of the root *might* be from fungus but any that survived to planting size, I planted. The red "lesions were on the sides of the rootlet and of odd shapes.

I put a tablespoon of household hydrogen peroxide (3.5%) into 16 oz. of water.

I think it puts oxygen around the root where they need it and it kills bacteria. I intend to add it to all flotations I do.