Look likes you got a bacterial bloom or algae bloom.
There's nothing to do with
bacterial bloom, this mean you may have a cycle trouble. The situation will resolve by itself in 1 week. I would monitor ammonia and nitrites if I was you.
But
algae bloom is caused by excess lighting.
What's your photoperiod, sometime algae bloom (green cloudy water) looks like a bacterial bloom (white cloudy water), and it's cause by excess lighting. So photoperiod = How long you keep lights ON versus OFF ? Are you on a timer for lights ? I had this problem when I added powerfull lighting system to my tank, here a picture of my tank two years ago:
The water look like white cloudy, but after I put some water in a white bucket, we can clearly see:
I can refer you to the old thread I started :
http://www.aquariumadvice.com/forums/f12/water-is-very-very-cloudy-275351.html
For the white thing on your vals, I don't know what it is... I would have say staghorn algae, but it's too white.
UPDATE: After few researches, I conclude to staghorn algae lol:
About PH and CO2:
PH is not causing that, don't but CO2 only for PH, this is a very bad idea. Before going to CO2, analyse light you have, tank size and deep. Also the CO2 won't work if you don't have a canister filter.
Give us your KH° value, and I'll tell you if you got a normal PH according to the KH. Don't try to lower PH using PH-, you may kill your fishs. Also CO2 won't drop as much your PH as you think... In my case, dosing tons of CO2 drop my PH from 6.8 to 6.6... Not a great change for a low KH tank.
What's your tank size ? And what lighting system ? (Watts, fluos?, T5 or T8, maybe T5HO ?)
Can you awnsers theses ? I will calculate your light/tank values.
Exact tank dimensions (I mean the HxWxL)
What's photoperiod?
What's lighting system?
Timer?
Water KH°
Water PH in same time testing KH?
Ammonia reading ?
Nitrite readings ?
