We used to have a large Ikea pendant lamp that had a counter weight on a very thin line. You could raise and lower the lamp very easily and the weight was hardly visible(looked like a slim fishing line sinker). When the lamp was up high, there was a slight loop of the cord, but not unsightly. I wish I could give you more technical info, but DH is the engineer in the family LOL. Hope this helps with an idea.

Knees and hips are in vogue---and have become so regularly done us old folks think one day to consider replacement of something that has worn out its use.

With such operations one of the items you are recommended to purchase and practice using is called a "reacher"...a simple trigger-like on one end that squeezes a lever on the other end. Works by wire.
It is a very effective tool when one cant reach due to restriction after an operation.

With this, I use a plastic cup (comes with the liquid laundry soap)...it is stout and will withstand the squeezing of the tool. I use it regularly to put birdseed in my hanging feeder outside --without taking it down which would be a chore since there's a foot of snow on the ground.
I would imagine it would work just as well with water...as long as you use care in reaching and upending over the pot.

The "reacher" can be bought at any store that sells such paraphernalia of post-op supplies.
My dealer had two sizes....long and longer. The shorter of the two I think does adequately and bears no weight on the arm........cost is about $15.00 - $20.00.