I'm assuming the fermenter itself isn't 5 gallons, but rather the usual 6.5-6.7 gallon bucket? Because if you filled a 5 gallon fermenter to the 5 gallon line, no wonder it's constantly erupting over. But given the beer, it's not surprising that it'd be a violent one either.
The bucket isn't 5 gallons. Prob 6 or more. Lots of room north of the 5 gallon line. Just measures for a 5 gallon batch. Sorry for misunderstanding. I'm new but not dumb enough to fill bucket to brim!
On the blowoff tube, my biggest concern is there isn't s tight seal at the hole on the lid of the fermenter. How do I fix that or does it not really matter? I suspect when the yeast is really going it doesn't matter but later Id be worried about air going in
I usually switch back to an airlock filled with Star San or cheap vodka after the first 3 or 4 days. After the violent fermentation has subsided you shouldn't have any problems.