Dumb plumbing question

DmitryB · 2026-07-03T13:04:33-0400

Got a dumb plumbing question: was watching a BRS video on the Triton ATO tank (which I bought) and he attached 2 adapters to the hose - no doubt it's something simple, but what is it? One is right at the pump and the other before the hose leaves the reservoir.

Reefering1 · 2026-07-03T13:07:41-0400

Look up "John guest fittings".

tbrown · 2026-07-03T13:08:05-0400

The one at the pump looks like just an adapter to go from the pump outlet size to RO tubing. The one at the reservoir is most likely an anti-siphon.

DmitryB · 2026-07-03T13:14:27-0400

Do they call that "check valve?"

tbrown · 2026-07-03T13:16:52-0400

DmitryB said:
Do they call that "check valve?"

No, it's just an anti-siphon. Check valves work but these are simpler. Basically it's a straight pipe with a hole in the side that sucks air so when the pump stops, it breaks siphon. It's a little more complex design but that's the basic idea.