Thanks for all the feedback everyone.
Currently I use a simple aquarium siphon to get pull water out and vacuum the sand at the same time. My sand bed is on the thin side (1” or less) and when I started out I couldn’t get my nitrates under 20 for a long time despite a low bioload. Then I saw a video of someone deep vacuuming their sand and decided to try it. Almost immediately my nitrates went down to undetectable levels. So that’s worked for me. I siphon into buckets which I dump into the laundry tub. The only reason I thought of the storm drain is because of the gravity issue - a hose wouldn’t have to go up into the tub. (Thanks for making that point Frogger; I don’t want to do something that would negatively impact the environment. In fact that’s one of the reasons I don’t do RODI but that’s a whole other can of worms) I would like to continue vacuuming my sand, but I just want to eliminate the treks back and forth. Yes I’m lazy. You’d think the exercise would do me good
So perhaps I could siphon into a large bin, then pump that waste water into the laundry tub? Is it simpy fitting a pump onto a long hose? (This occurred to me as I recently watched the pump work on my return line, first time using a sump - I am learning something new every day haha). What kind of pump would I need?
I’ve thought of the Python - wasn’t sure how it worked. Maybe it would be easier to buy one of those instead of trying to jerry rig something myself. But would I still be able to vacuum my sand in the same way?