I prefer to have several pieces in rotation, so I don't have to clean as often but when I do clean I clean several pieces at once. I'm sure some people prefer the exact opposite but that's what I have found works for me.
Not sure if it's different now, but 15-20 years ago that's how mine and all my friends' looked. You could start with a clean one and it would be dirty as fuck like 3 hr later. We would just change the water a lot but only clean them every week or two.
Or just squirt some rubbing alcohol into it and give it a shake every once in a while. Cleaning your bong isnāt hard, and if it has gotten to this point it makes me question how clean you keep everything else around you.
I can only suggest to use isopropanol (not sure whats the english word but i think you guys will know). The good industrial stuff with high purity. You literally only need to fill you bong with like 100 ml, shake it around a little, rinse with it water afterwards and it will clean as fuck. I just cleaned my bong for the first time after many years and it took like 5 minutes to have it look new again.
Iām American and we also call it isopropyl alcohol but another common name for it here is rubbing alcohol (which is essentially a mixture of iso and water)
Iāve never needed anything more than that either. Tried plenty of gimmicky products back when I smoked but it never really made a difference. At best an additional abrasive but you can do that yourself as well if itās truly necessary.