If they keep coming right back, it's not working. It's probably just sending them into hiding for a day or two. I tried some home-mixed remedies with varying success, but the best thing I've found and the only thing that I can confirm works is 1) physically wiping every leaf off with a wet washcloth. You can get like 90% of the adult mites that way 2) follow up with an aggressive coat of insecticidal soap. I bought this stuff on Amazon, but presumably any similar product would work. remember that mites like to hang out on the underside of leaves and in nooks and crotches of the stems for protection, so make sure you're getting right in there from several angles. 3) Alternate between a spray down of the soap one day and cold water the next making sure the soap gets down onto/into the surface level of the soil too, that's where the babies are. After about a week of that, you should be just about clear. That worked well for me, at least! That soap spray is awesome, it makes short work of fungus gnats as well, and doesn't seem to hurt the plants other than leaving a slight waxy residue on the leaves after a few coats of it.
I've really never put too much thought into it but we do use this fertilizer that a fellow redditor recommended in a r/houseplants.
https://www.amazon.com/dp/B015EA6FXG/ref=cm_sw_r_cp_apa_fabt1_H52PFbB779JBH?_encoding=UTF8&psc=1
Check these command strip cord bundlers out! I bought them for Christmas decorations and ended up using them to stake up a Christmas amaryllis. My pothos isn’t quite at this stage, but I’ll bet these would work great!
Command 6 Cord Bundlers, 12 Strips, Each Bundler Holds up to 2 lbs, Easy to Open Packaging, Organize Damage-Free https://www.amazon.com/dp/B0797LMJF5/ref=cm_sw_r_cp_api_glt_i_ZE2SVC580QK92X7Y1D1R?_encoding=UTF8&psc=1
It's been in this pot since I purchased him back in July; it's a self watering pot I found on Amazon. I highly recommend them. I have all of my plants in them at this point.
https://www.amazon.com/dp/B07998PP1B/ref=cm_sw_r_apan_glt_i_3MZF8T2YA2K7DE3GSF8K
He came in a tiny little plastic pot nested inside a ceramic pot, so he gained quite a bit of root room in his current pot.
I used a mixture of 75% cactus potting soil and 25% standard potting mix and added the peat moss he came with back to the top of the soil.
Biggest thing is light; it gets it's own, and that really made a difference quick. It's under an HLG 100 V2 (https://horticulturelightinggroup.com/collections/all/products/hlg-100) so it's a bit spoiled.
The giant tray beneath has water, I have found it likes to be always damp, so wet fgeet aren't bad, as long as it dries in a day or two (and with how deep the pot is, it's probably more like wet toes than wet feet) this helps with humidity. We're in Chicago, and I never let the indoor temp go below ~71 f during the winter. Unfortunately I can't control humidity here like I can in my basement, so it's about 35% humidity during the winter, but it doesn't seem to mind.
Pretty much every care guide online hasn't helped. It's bigger than even the one in Garfield Conservatory (which makes it my crowning accomplishment because that place is magical). It didn't start putting out babies until just this last year, so don't worry if you don't get pups for 3-4 years.
I've found Growsafe to be THE BEST for spidermites (which used to be a regular issue on it) and it's great for all my other plants. Seriously, that stuff is worth its weight in gold. https://www.amazon.com/dp/B07M983TRL/ref=redir_mobile_desktop?_encoding=UTF8&aaxitk=5e4d0260e505478faecbb718f6a395d0&hsa_cr_id=2160929290001&pd_rd_plhdr=t&pd_rd_r=40a7e35c-f4a4-4866-a9ae-c809c8339ddf&pd_rd_w=dKDYW&pd_rd_wg=...
Beyond that, I water now and then with diluted to half strength miracle grow (24-8-16), because I'm not sure we'll ever be able to repot this monster.
tl;dr expensive dedicated grow light, moist-but-not-waterlogged soil, growsafe for pests, and generic miracle grow diluted for additional nutrients.