I use one of these, I hook it up and filter 10 gallons at a time into a brew kettle for watering and then put the filter back in storage.
Countertop Portable Universal 5-Stage Reverse Osmosis RO Purification Water System with DI Deionizing Mixed Bed (Close to 0 PPM) postfilter, Build in USA https://www.amazon.com/dp/B00GDGTKRY/ref=cm_sw_r_cp_api_i_8B5GP214QTFEXQN2G1WB
You want carbon for the removal of chlorine. There's some filters that attach to a hose. You could just attach a short hose to your spigot and fill from there. However those cartridges are pretty expensive around $30 a pop and you'll be replacing them fairly frequently. It'll be more cost effective to buy a Brita and just use that.
I understand you can't use an under sink RO system, but they do have counter top system that can be quickly attached a detached and used as needed. I would assume if you purchase the right fitting or an adapter you could use it with your spigot as well
I'm not recommending this product specifically. This is just what showed up first in a Google search.
As for the pink stains in your bathroom. It's not hardness. Hardness is caused by minerals like calcium and magnesium. It causes scaling which will look like white crystals around a faucet. What you have is a type of bacteria. Hit that stuff with some bleach and bleach your bathroom/toilet frequently. It sounds like serratia marcescens. While it is a bacteria it's not dangerous but it is unsightly and gross, but it has nothing to do with your quality of water
Yeah that sulfur smell is sometimes caused by bacteria in wells that consume the oxygen in water. So your water probably has low amounts of oxygen to start with, so aerating your water will help your grow regardless if thats the issue or not.
I got mine off Amazon. I got a cheaper counter top version. Just make sure you dont get one that adjusts pH or adds nutrients back in. 6 or 7 stage ones sometimes do that.
Countertop Portable Universal 5-stage Reverse Osmosis RO Purification Water System with DI Deionizing Mixed Bed (close to 0 PPM) postfilter, build in USA https://www.amazon.com/dp/B00GDGTKRY/ref=cm_sw_r_cp_apa_i_dDjBCbM98TB73
here is what I use. I pair it with 2 7gallon jugs to capture the water and a cheap TDS meter. Been using it for over a year. You need to change filters and I think for this system they're around $50. The change frequency seems to be based on usage (not fully sure how many gallons). I have yet to replace my filter - every time I use it to collect water I use a TDS meter to check PPM, once I notice that it gets over 7-10ppm I'll change the filters. My tap water is something like 200-250ppm, this gets it under 2ppm, usually 0ppm
Countertop model, if the little woman won't complain loudly about it. :)
I use this
Replacement filters are about $50. I have mine running to a40 gallon storage tank with a float valve for shut off. Works great.