I bought a shower head filter that is about five inches in diameter. I also use a nice Delta 3 position toggle valve. Reducing it down to a 3/8 flex hose for enema works, i will apply it without nozzle by causing it to squirt thru, us a standard girl's white 8 hole douche pipe, or a 20 inch X half inch diameter colon snake with 8 radial holes set into the tip with a leather punch. Don't need to blow out all the gory details. If you go for it, consider taking off the shower drain cover and practice careful sanitation.
Planning to find reference to some of the critical parts, that especially are not typical and add them in onto this post.
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Delta 3-Way Shower Arm Diverter gives, a shower, or shower n hose, or just hose only.
(a must have in my opinion)
Sprite Showers Universal Shower Filter in Chrome bought locally
or another similar, there are several kinds.
Filter is applied to end of hand shower hose with transition tubing following. Remove to drain and dry after.
1/2 in. NPT brass with 3/8 PEX Barb by Watts as an example will adapt your tubing to the shower filter.
The more creative you are, the more you own this setup.
General Tools Model # 72 leather punch, using its smallest or next to smallest punch.
I can't find the colon tube i bought 10 years ago. But it is translucent, half inch thick, semi soft and open ended. I plugged it after punching fine radial holes half inch back from end. originally from OptimalHealthnetwork