High nitrates

[kristiananderson at att_net]

Has anyone else had problems with high nitrates in their city water supply?  
Iowa has had a reputation for this, though it wasn't much of a problem until I 
got my new lighting system.  I mixed up a batch of PMDD and and the algae 
started to grow like crazy.  It was only later that I actually tested the tap 
water for nitrates and found very high levels.  Right now I'm diluting the tank 
water with water from the dehumidifier to bring the levels back down , plus 
I've picked up some black mollies (who just had 15 fry last night!)and ottos to 
hopefully take out some of the green hair algae in the tank.  I have to say, 
though, with 110watts and CO2 in a 29 gallon tank, the plants were pearling 
like there was no tomorrow, with bubbles streaming to the surface all day 
long.  Unfortunately, the algae is now pearling!  Other than getting the 
nitrates back under control, any suggestions?

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