Rainwater toilets and greywater showers: City tries new water-saving tricks

I’ve run into that same issue with “natural” soaps leaving a weird film, especially in showers hooked up to rainwater or greywater systems. Hard water just makes it worse. If you’re using rainwater for toilets and showers, are you filtering it before it hits the fixtures? Sometimes the sediment can speed up buildup, and I’ve seen folks skip that step thinking rainwater’s already clean. Curious if anyone’s tried a multi-stage filter or just stuck with basic mesh screens?

I've tried both mesh screens and a basic sediment filter, mostly because I was worried about gunk building up in the pipes. Honestly, the mesh alone didn't catch the finer stuff, and I still got that slimy residue in the shower. Ended up adding a cheap spun-poly filter as a second stage, and that made a big difference with soap scum and buildup. Anybody ever notice if those carbon filters are worth the extra cost for shower water? Not sure if they're overkill or actually useful.

I’ve messed around with carbon filters for shower setups. They’re decent at taking out odors and some chemicals, but honestly, unless your water smells funky or you’ve got skin sensitivities, it might be more than you need. The spun-poly does most of the heavy lifting for particles. Carbon’s more about taste and smell, which isn’t a big deal for showers unless your source water is rough.

I get where you’re coming from, but I’ve seen a few cases where folks skipped carbon and ended up with weird skin reactions after switching to greywater setups. Not always about smell - sometimes it’s trace stuff you can’t see or smell that causes problems. If you’re dealing with non-potable sources, I’d rather overdo it than risk a callout for a rash or worse. Just my two cents.

I’ve actually wondered about that - like, is carbon really that necessary if you’re just using the water for showers? I helped on a job where they skipped the carbon filter and the water looked fine, but after a couple weeks, one of the tenants started getting itchy skin. No weird smells or anything, just irritation. Makes me think there’s more going on than what you can see. Is it always trace chemicals, or could it be bacteria too? I’m still trying to wrap my head around all the stuff that can sneak through.