How to de-scale a loo that is connected to a Septic tank?

well it does, but only some of them

Septic tanks are bloody big and full of water

And the Ph soon neutralises and s*it is full of new bugs

Not really a septic tank, more of a cess pit.

Right, you've just described a septic tank. Sometimes these apparently have two chambers, but I'm not sure why.

Mine had THREE.

And it was still crap. The replacement Klargester that ensures aerobic breakdown is infinitely superior.

The tanks are a crude way of getting better and better settlement of inorganic sediments and such solids as may form.

The Natural Philosopher posted

Is there not a risk that the acid will erode the siphon washer and cause a leak?

Yeah, but are you a DIY-er or a snowflakery wuss?

replying to The Natural Philosopher, Guru wrote: Check out Vulcan, its a German product around for some 40 years in industry. Its NOT magnetic and works for my whole house. I installed it and its brilliant, saw huge improvements with limescale in the toilet pans, shower nozzles and heating as well. Its totally safe to use with septic tanks - no chemicals or descalers ever

It's the old wire round pipe scam. Despite being magnetic it claims to not be magnetic.

NT