Hey dude... Welcome to the UC world. These are by far the best system plans, as well as the rest of the fam here is amazing for helping with any issues you will run into...
Run 1/4" line for your top off to epi bucket float. I use the green Floraflex line on everything. It's softer than the black shit so if I disconenct a line from a PEX fitting then I cut off a half inch prior to hooking back up otherwise they will leak. You may be using different line though... IDK about those fittings there... Mine all came as one piece you thread apart... I'll have to look but I can't remember if I put an O-ring in mine or not. I don't think I did..
ZAOJIAO 1/4" Tube Bulkhead Connector Push Fit Quick Connect for RO Water Reverse Osmosis System (Pack of 5) in Pipe Fittings.
www.amazon.ca
Your also fine running a "T" out of the epi bucket. I asked the same question to Heisenbeans since I was dealing with space restraints from being in tents as well. I even made my connecting pipes between the buckets shorter than what was in the videos but ran into issues when I went to assemble. Edibles and building aren't a good combo for me. I was also going to put my epi outside of the tent, but ended up just staggering it back a bit as you can see in the pic below.
The systems are insane dude.... Looking forward to seeing your build.
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