PH Help..

There are not any reliable methods of changing pH chemically. Instead, you need to use a reliable method such as adding some crushed coral to the tank, or using peat filtration on the tap water. However--you should figure out why your tank water is so much lower. Are you running CO2 on this tank? How often and what size water changes to do you? Is there something in the tank that is lowering it's pH?
 
Ditto on what OG said.

I don't know how you keep your ph down, but I'd like to know you secret :p.

Could there be some gas that forms a basic solution when dissolved in water?
 
I had to raise my PH and did it successfully. I bought crushed coral from a local pet store, along with small thin bags. I forget what they are called but they are with the fish stuff. Put the crushed coral in the bags tie a rubber band around it and but it on top of your foam pads in your filter. This raised my PH. Just make sure you measure it often so it doens't raise too much or not at all stuff like that. ;)
 
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