Bryan at VDH has a write up about the washing machine for hoses.... I just wash them in the sink with dish soap, and rarely a long, soft bottle brush (like for cleaning a CamelBak).
On rare occasions I also clean the inside of my hoses with a bottle brush. But I still think that drying the inside as soon as possible is the best way to control any potential growth.
OK, I am not a biologist… not even close…
My observations is from cleaning and drying wetsuit and wet suit booties are that the quicker I dry them (with blowing air) the fresher they stay and the less they smell. This was particularly true with my old kayaking booties. I tried many different chemical and cleaners, but drying them quickly with forced air worked much better that anything else.
I am obviously making several assumptions by directly relating the smell with biological growth… so please correct me if I am wrong. Note: Fresh water diving (or kayaking) appear to produce the strongest biological load and smell if not rinsed and dried.
In any case, my hoses never smell, but I am still under the impression that by drying them with gentle forced air it will not give much of a chance for bacteria to grow.
Note: I am totally open to some knowledge by someone that actually knows something about biology.
Added: for wetsuit, Sink the Stink does seem to help a lot, but I still use some form of fan to dry ASAP.
For hoses, I would not use anything stronger than dish washing soap.