poshate - is 0 too low?

[pascal32]

Seems that in the last few months I have lost some SPS color in the tank. As of late the blackout contributed, however the trend was established prior.

I picked up a hanna checker for phosphate (the regular, not the ultra low range)

The accuracy is listed as .01 with a +- of .04

I consistently ready 0. I tested some tap water and read 0, then .04 after letting the water run for a bit before taking the sample.

Reading around I'm not of the belief that 0 is a good number - what is a good number to aim for in a mixed reef?

 

[toddmh]

how are the Nitrates? I'm pretty sure when I took my water in at ARC to be tested,I was told if you have really low phosphate reading..they might be locked up in algae or even the rock in the tank

 

[Steve Canyon]

I'm of the understanding that tap water at 0 can't happen. I suspect something is amiss.

 

[superkat]

i'm of the understanding that tap water at 0 can't happen. I suspect something is amiss.

+1

 

[mr.maroonsalty]

There is some speculation that true .00 PO4 may not be a good thing especially if absorbed all out at once hastily. How long have you had the corals that are losing colour?

 

[pascal32]

There is some speculation that true .00 PO4 may not be a good thing especially if absorbed all out at once hastily. How long have you had the corals that are losing colour?

The colors have been fading over the last couple months. Growth is fantastic though! I do run gfi and carbon pretty aggressively.

The tank is pretty new (4-5 months?)

 

[pascal32]

I'm of the understanding that tap water at 0 can't happen. I suspect something is amiss.

I suspect the same, that is why I tested twice. I'll do another round of the tank and tap tomorrow

 

[der_wille_zur_macht]

Does the meter have any sort of calibration capacity?

Truly zero phosphate would be a bad thing (your livestock needs it, just in extremely low concentrations) and rapid changes of any parameter can be a bad thing, but even if that meter were reading accurately, it's probably not low-range enough to actually distinguish between a "healthily low" value (like, .0005ppm), and actual zero.

Even if your source water was zero phosphate, you'd be adding a fair amount every time you fed. What are your export methods? GFO? Changed it recently?

This is a good place to start:

http://reefkeeping.com/issues/2006-09/rhf/index.php