Anyone have tips on how best to look after our outdoor cesspit please? Like what soaps / detergents to use etc.

Sorry if it's an odd question but thought I should ask as heard they can 'retaliate' if not looked after properly...

Since nobody in the know seems to have replied, I will put in my two pennies worth.

We never use any of the usual loo cleaners (Duck, etc). That can stop the system doing it's job. You can get good loo cleaner that is septic tank-friendly from the Green Shop and it's not wildly expensive when you consider how much it costs to empty a tank. These days, you can also get most of that stuff in a big P&S. Not sure about Welcome.

For washing machine and sinks, we have a separate grey water tank so we don't always worry about using friendly powder or washing up liquid, but you could consider using something, also from the Green Shop. However if you share a tank you don't know what your neighbours are putting in. I am assuming you have your own, so it's worth the effort of thinking about the suds you put in.

We never ever use bleach. You can also get tank-friendly whitener from the good old Green Shop. Actually, if you asked in there you might get some useful advice. Sorry I can't think of any more. Good luck.