is the uneaten food and waste youre talking about just unsightly or is it throwing your water parameters off?
If the answer is the first, then a siphon or python would be fine.
If your answer is the 2nd, the best solution would be to have (if you dont already) more than adequate filtration, preferably a sump to solve the issue.
I have a 265 with overflows and a 55 gallon sump with bio-balls in my overflows and in 2 spaces in my sump and when I had a stock similar to yours, I never vacuumed anything. There is too much water for that little bit of food or waste to screw with your water parameters if the filtration is setup correctly. All I do is 50-60% water changes weekly and change the media pads at the same time...and I havent had a single issue with parameters out of whack at all...ever.
I currently have moved my pairs of fish to other places and even with the bioload I have now and no vacuuming, they are stable and about as good as it gets.
One reason I dont vacuum is because I have about 100lbs of driftwood, 200+ lbs of rocks and until last week, tons of live plants. For me, I dont see the waste because the aquascaping and the powerheads keep it out of sight, usually under the driftwood.
Now, i do vacuum roughly 2x a year if it needs it, but the waste and uneaten food gets broken down eventually and has never been an issue.
All that being said, i dont know if you dont have overflows that this will work for you. I dont have any experience with any other setup this large without overflows.
Good Luck...and good to see another NC MFKer...whereabouts in NC?