We were asked to go and clean our local hockey club showers last year.
Evidently the girls were complaining about the state of them!
We used a product by a firm called Clover and its called Breaker. Comes in 5l or 1l. Its brilliant, sticks to the walls as its quite thick so you can scrub all the cr@p off,or you can dilute it as required.
For the floor we used a polyprop scrubbing brush on a long aluminium pole that really gets into the grout (get 1 from janitorial supplier) and then a floor scrubber with a green pad on to agitate.
Remember to use a circuit breaker on the machine as you are in a wet area, mask and gloves because its an acid (hydrofloric/chloric).
And just rinse it down the drain.
Re the sx12 on the link I am looking to get 1 imported from the States at the moment but no real success, any ideas any one?
Murky