Tap water & nitrates

[pashari]

From reading many of the posts I gather that using tap water is a huge no-no in the hobby. I have a FOWLR 60 gal and have, for the most part, used tap water. Granted, I treat the tap water and then areate the tap water for 48 hours prior to mixing with salt, but it still is tapwater.
If a poster comes to you with a high nitrate problem you would initially suggest that the tap water was the culprit. I have just tested my tank for the first time in months (hanging my head in shame) and find that while pH is normal at 8.2, Ammonia is at 0, Nitrite is at 0, my Nitrate is pretty high at 40 ppm. So it would go that doing a water change with tap water really wouldn't help solve my problem.
However, I just tested my tap water and there are no Nitrates. Zero. Zilch. Not even a hint.
Now, if I had a reef, with its more sensative corals, I could understand not using tap water even if there are no nitrates. However, in a FOWLR what would be the harm? Obviously, I do treat the tap water and, as I said, areate it for 48 hours prior to mixing.
Is there something here that I'm missing?
Thanks!!!
lisa

 

[jupoc911]

tap water usually does not have nitrates. It does however have other metals in it, phosphates, and silicates in ir which will cause algea blooms.

 

[anthonynyc]

Being new to this hobby let me give you my perspective.
I started by using tap water but after reading the posts on here, I started using RO water from a friend who has the unit.
Initially I had a HUGE amount of brown algae in the tank, it looked horrible. It went away after about 2 weeks. I did not use tap water since then.
A few days ago I removed 10 gallons of water (72 gallon tank) and did not get a chance to go to my friends house to get the RO water so I just added the tap water.
Guess what, the tank is COMPLETELY brown again, all over again. The levels are all on the 0 including nitrates and nitrites but theres something in the water that this brown algae loves!
I will not be using tap water again.
Anthony