Very much agreed. It sounds like cyano-bacteria and most likely the clone are too far gone. If it were rooted plants you could have more time. Look up cyano- bacteria and bio-slime. it can embedd in you equipment.
I struggled with this for a long while and kept changing equipment regularly. Problem still there. I was using a garden hose to was everything in between grows. Guess what ? It seems to like hoses, so I just kept bringing it in not knowing.

Good news for me was E.M. ERYTHROMYCIN. ANTI-BACTERIAL FISH MEDICATION. It will take care of it almost overnight. Get it at the pet store. it comes in little packs for 10 gallon each. mix as directed. will not hurt plants or fish.

I ran it once and being more carefull how I clean up it has not come back. this was amazing.

the whole problem is not enough good bacteria to keep the bad in check. Running a worm casting tea is the proper organic way to keep it good and have alot more bene's in the mix. Or you keep it laboratory clean.

it 15 buck to try it and won't hurt anything.