We probably don't vote the same, but are fond of each other, and share interests (pets, sense of humor, etc.) other than the tuba. We also send each other messages - occasionally chuckling at what someone paid for this-or-that on eBay, etc.)
He picked up on my quickie/hillbilly tuba cleaning method, and has posted pictures of himself using my method (via his social media page) standing out on his driveway - just past his garage...probably access to his water tank from there.
It requires a REAL RUBBER garden hose (as heat will cause any vinyl hose to come apart at the ends...and - not only will the hose be screwed up, but - a person could also end up getting scalded.

...so I remove the main slide, and jet HOT water through the instrument while (enthusiastically) wiggling the valves...and not just for a few seconds...probably for at least a minute.
Most (probably not 100%...) of the green slime gets knocked loose and ends up (either) on the ground (or - the way I'm doing it) going down the utility tub's drain.
me...??
I use a salvaged washing machine connector hose. Both ends of these are female, but available for sale is a double-male-hose-threads thingie, which converts those into short/high-compression/"regular" hoses. I fasten an (all brass/old-fashioned hose nozzle and "jet" the hot water into the mouthpipe and out the main slide (small size) tube. (again: the main slide is removed, so as to not fill up the tuba - past the valve section - with water.
This isn't any sort of "perfect" cleaning job, but it knocks a large percentage (most of...?? a bunch of...??) the slime out and without removing anything from the instrument other than the main slide. I know for a fact that those disgusting "slime tabs" (which form in the porting next to casings, as well as the porting within pistons and rotors) can actually LIFT (when blowing air through the instrument) and (yep) can contribute to (or CAUSE) missed attacks.

Mrs. bloke helps me hold my tuba upright in the faucet-outfitted utility tub (bottom bow on a towel) while doing this, but I'm considering running a hot water faucet to the outside of the shop (some people are having these included on new house construction, these days), so I can just rest the tuba outdoors in the grass (ok: maybe on a towel in the grass), and won't have to be so careful (having to avoid indoor obstacles).