On the job yesterday, my own spotter that i got from Nick at solutions so it's not that, I agree with Joe, many things can cause foaming issues, but the amount i have been getting where i have to stop several times to empty tank add more defoamer, and still it is making enough foam to affect vacs just doing one lounge

i would think is highly abnormal and something is very wrong somewhere.
Air getting in is my first guess, so i have stripped the old seal that had in fact creased so may have been the cause, i am going to put some flexible mastic on it then hope that will fix it, it has also been stood on the kitchen full of water with newspaper underneath to see if the tank has a leak, i will check the seals as suggested too.
I am also going to call the engineer at cleansmart to discuss and will raise the possible diagnosis's suggested on here.