Hey you deffinatly shouldn't bother with the tap filters they are just a carbon filter so your phosphates will remain. You can buy a cheap RO
system from the internet for usually 100$-125$ 3stage is plenty with a 3 gallon tank that will produce 50 gallons day just fill your own jugs it will pay for itself in 20 bottles from the store. If your on city water you only need to do filter/membrain changes every 3 years. IMO
well worth it plus you dont have to lug bottles around and waste gas getting them.