[robert meldrum]

I recently left a couple of gallons of waste water in the return tank ( it was raining very heavily and don't work weekends ) Anyway, opened the empty valve and the blackest smelliest waste I've ever encountered came out.

What I'd been using was a sample of a colloidal product. As I've never encountered such fithy waste I wondered, why was it so black and why the unbelievable smell.
At first I thought the carpets must have been incredibly filthy but it's a regular customer and a " clean "one.

I deliberately left some waste overnight a few days ago after using the same product as a prespray and got the same result.

Was this just an example of colloids at work ( holding the dirt in suspension ) but what about the stink which was really vile. Got me thinking about a few recent posts on " smelly carpets " and the importance of thoroughly rinsing out chemicals and getting across the importance of achieving the minimum possible drying times.

[Simon Gerrard]

Robert,
If you leave your tank full overnight a lot of the sludge on the side of the tank softens and falls to the bottom of the tank in the form of a sediment, which is where the smell comes from.  I very much doubt it is anything to do with the chemicals you are using.

Simon

[robert meldrum]

Simon

The tank is stainless steel and curved, also vacuum out at least weekly. The only job done with the clean machine was a regular " clean " house .

Never used the product before which cleaned very well but I left about 2 -3 inches in the waste tank as it was pouring when I left the job. I forgot to empty the tank completely and it lay over the weekend with the above result.

I have often left waste in the tank in the past without this happening when using standard chemicals which leaves me to believe it's the colloid product that's caused the stink NOT because it doesn't work but because it continues to work when in water.

[derek west]

its not the chems, i think its bacteria, (like mould on a wet carpet) only guessing though. it happened to me a few weeks ago, the whole tank from start to finish was black water when emptied, right down to the last drop, all i used was powerburst and acid rinse.
derek

[Gerry Styles]

That would be from bacteria forming in stagnant water, more noticable in hot weather. That happened to me and I almost lost my breakfast when I smelled it Just need to flush the tank well, add a drop of jeyes fluid to 5 litres of water and leave in the tank.

[robert meldrum]

Bear in mind this was a colloidal cleaner which should actually kill bacteria. Anyway it's something that's never happened in 25 years using " regular " chemicals so just wondered if anyone had similar experiences with colloids which may just have been behaving the way their supposed to !