Connect the elbow to the cup and slide a hose over the barbed end.
Then put the other end of the hose inside a 2 liter bottle.
No more checking it every day!
I have an Oceanic 75g RR tank, MegaFlow sump, ASM G2 Skimmer, stand, canopy, and 60lbs of base rock.
Someday I'll add fishies.