white precipitate in tank water

Hey folks. I just started a new 29g plant tank and all seems well except recently I 
noticed that my tank water has turned cloudy! There seems to be a white 
precipitate floculating out of the water. I noticed this cloudiness about 1 week 
after I began to use some PMDD a friend of mine mixed up. Has anyone out 
there experienced this? All of the plants and fish are very healthy and even 
thriving. The tank conditions are: pH 7.0, GH and KH 7 degrees hardness, temp 
80 deg. F, 30 W fluorescent light (I know this is low), CO2 supplementation. 
Unfortunately, I know very little specifics about the PMDD at this point, but I will 
find out. I was adding 1 ml of the PMDD mix once per day. Any and all 
suggestions would be appreciated. TIA!

Robb D. VanPutte
Dept. of Biology
Texas A&M University