Need help with possible efflo problem on tiles in pool room.

[John.Harper 14]

Im set to do a demo in a hotel for their enclosed pool area. The tiles have a white stain over them, its pretty uniform. It does dissappear with water. Three other guys have been in to demo it over a 2 month period and none of them can touch it even after multiple attempts but from what i heard they were trying to use pressure and one guy even bought in a floor buffer to clean it i think im going to be the first soft wash guy to touch it. I just wanted to know if anyone else has experienced this same problem. The hotel management is baffled over the stains and if i can clean this up for them i will be their hero and it will get my foot in the door for quite a bit of work hopefully. I was going to try to use a strong mix of oxalic acid and i am going to give a call to eacochem but if oxalic will do it then thats what im going to go with because the demo is set for this wednesday coming up. Thanks in advance you guys are awesome!

Edited March 11, 2012 by John.Harper

[John.Harper 14]

Nobody?

[mick m 19]

Hi John. It almost looks like years of constant cleaning with a biocide type bleach has finally caught up with it, Is it in a high foot traffic area?

[James 624]

Looks like some wrong type of chem has etched the surface. No what type of stone before using an acid.

[John.Harper 14]

the hotel has been around for 10 years but they built two extra floors on it and the state finally let them open up .. they have been open for 4 months now from what i know i but dont think it has been cleaned before just small test spots from other contractors .. im really not sure what the substrate is but it is some kind of odd stone .. im going to call eacochem today and see what they have to say

[Cat Powerwashing Inc. 17]

Looks like someone done f----- up! your probably gonna have to get some samples from a chem supplier and do a test spot to see what works best. sureclean sent one of their reps out for me.

[Craig 111]

To me it looks like phosphoric acid burn. What kind of tile surface is it.. meaning like a glazed tile or more like an aggregate or porous surface? I can't tell from the pictures. If you had a nice clean close-up I could probably tell you what's going on. If it is scaly and you can chip it off by putting a knife underneath a layer it might be Calcium or Calcite from hard water.