DIY background (in progress)

Did that tap sample sit out overnight in a shallow dish?
 
Before I am going to buy fishes, I have some question to ask here..

--Will african cichlids nip on my background, I heard someone tell me
they will, is that true?
If they dont, will they be fine with my horseface loach and upside-down catfish?

--Can Harlequin Rasbora be kept in a high pH tank?
 
I have never let them cure in dry air...
The first week is by moisting it with wet towel..
and followed by submersing it underwater..
 
AquariaCentral.com