Even if the temps get high, 25-26 with air and root stim you'll be ok esp in the first part of the grow, when it becomes a jungle in the bucket is when you have to worry about the slime, get some hydro bennies to offset that(root stim is ok, but the bactéria will compete for niches with the fungus), and you should be able to handle some heat. Iwould say to go for some silicone, but that just plays havoc with pH and for a first run, I would not recommend it just for the hassle. Can't wait ot watch this one unfold, wish I could be with you guys on the AWW grow, but I'm on the bench for this one!!!!