This is the third post for me, and I have not recieved a single response to any of them, so if I get something out of this one, I'm gone.

I am switching to a 125gal. tank from a 55 gal. I want to transplant the fish, and start using natural plants, but I have two good sized (3 1/2") silver dollars and a large (6") Bala shark. Is it even worth me moving these guys or will they just eat my plants?

Also, I have considered CO2, but am wondering if it's worth the cost? where to get a good deal (online)? how big of one I would need? what kind of maintenence is involved? how do you maintain your Ph level?

Any insight would be appreciated.