Freshwater pH problems

So while I was at school, my parents started up a freshwater planted tank. I told them to wait for me to get there and help but they got a little anxious and now they're having problems. They went and got rocks from the creek in our backyard and boiled them per the instructions of the LFS. They also got some driftwood that apparently turned the water a tinge of red for awhile. Well they got the red cleared out and let the tank sit for about a week and then got some plants, a lot of plants. The tank is now fully stocked with about 12 different plants, it's a 36 gal tank. Now their pH is up around 7.8 and the plants are turning brown. I had them remove the glass cover that was on the tank I advised against. They're trying a pH regulator to bring it down but it's not working, neither are water changes. The tank is heavily aerated with two large bar shaped air stones and a HOB filter rated for 50 gal. They are also using RO water from Wal-Mart and I'm trying to convince them that an RO/DI unit will be their best bet. Any ideas as to how to bring the pH down?

 

Here's a picture as well. Other than some of the plants turning brown, the tank looks really nice.

 

Remove the aeration bars for starters they are unneeded in planted tanks. That should help because it is gassing off the CO2 through surface exchange. Then lets see what happens after that. Should be in better shape then.

 

Alright, I turned off the aeration bars. What about the bubbles from the filter return? Should I leave the level low enough to allow it to put bubbles in or raise the water level?

 

Raise the level unless you have problems the other direction.

 

I would raise it. In planted tanks, you should shoot for as little surface movement as possible, since you want a bit more CO2 than your average FW tank.