HMA water

Whats HMA? heavy metal axe?

I dont have one.. sorry.

excerpt from link
http://ezinearticles.com/?The-Water-Parameters-For-Discus-Fish&id=655945


The RO filter will remove 99.9% of everything in the water, making the Ph around 6.2 depending on where you live. The HMA filter will remove the heavy metals and the Chlorine, which are extremely harmful to discus. The HMA will not alter the Ph which is ideal, because we can use that to blend with the RO water to make the correct Ph.
 
So RO water is acidic? Oh boy...not bad enough to make an impact when it comes down to top off water though I guess...
 
AquariaCentral.com