In retrospect, this should have been obvious to me but I didn’t think of it when I was assembling my plumbing on my overly complicated new setup.
So consider this a public service announcement so that others don’t make the same mistake: loc-line (modular hose) is not watertight and is not intended to be used for above water applications. The modular elements are just plastic on plastic and will leak if you have enough water running through them. Not a problem if you have everything fully submerged on the water side, but not ideal if you’re trying to span any distance through air.
So consider this a public service announcement so that others don’t make the same mistake: loc-line (modular hose) is not watertight and is not intended to be used for above water applications. The modular elements are just plastic on plastic and will leak if you have enough water running through them. Not a problem if you have everything fully submerged on the water side, but not ideal if you’re trying to span any distance through air.