Septic tank covered in foam :-(

[flanagaj]

I looked out of our static caravan this morning to see the below 😞

 

can anyone advise.  We have a 7PE tank and it’s just my wife and I.

 

 

[Bonner]

What does it smell like?

[markc]

I’m guessing detergent .. looks too white for anything else

[Mr Punter]

Have you used washing up liquid?  Maybe the air treatment has made it bubble up.