Industrial strength bathroom tile cleaner?

[JeffersLos]

There's an old guy living alone near here, that people are helping.

 

We saw the state of his bathroom wall tiles yesterday and they were almost crawling.

 

We masked up and used the main brand tile cleaners such as magiclean and mister muscle that spray on, then you scrub them 10 minutes later. 

 

They helped a little bit but there's still grime and stains on them.

 

Are there some industrial strength chemical cleaners that people can buy and use, some sort of acid based cleaner, for example?

 

TIA.  

[VocalNeal]

I use Vixol Oxy.

 

[carlyai]

5 minutes ago, VocalNeal said:

I use Vixol Oxy.

 

We're not talking about drinking here. ????

[lamyai3]

Promax should work fine, the white bottle. I also had good results with a cheap Chinese brand from Mr DIY (hydrochloric acid based). Be careful, if you leave it on for too long it'll dissolve the grouting. 

[JeffersLos]

1 minute ago, lamyai3 said:

a cheap Chinese brand from Mr DIY (hydrochloric acid based)

Thanks. I'll try that.