How to test po4 in rodi

[NanoReefWanabe]

Do I just buy a fresh water kit? Can I use my hanna phosphorous meter?

My tank has been wildly fluctuating between 40 and 7 ppb.
Everytime I get a high reading I open the valve a bit on the phosgaurd reactor, everytime it is staggering low I closed the valve a touch...honestly getting tired of messing with it..today I test my freshly made fritz RPM blue batch...hanna says 60ppb...wth...

I assume it has to be my rodi but both meters on it read zero and my di resin is still blue.... so I am at a loss here...

I dont really want to pay for an icp right now for both my tank and rodi, but I guess that is the only way to be sure...

I plan on switching to (i believe) aqua forest's phos.04 product to try and regulate my po4 at .04, as it seems phosgaurd is all or nothing when it comes to removing po4.

 

[Sk8r]

You wouldn't be feeding green food, would you? That can hand you phosphate.

 

[NanoReefWanabe]

I have 35g cube with 20g sump roughly 45g water volume

I feed reef roids (broadcast) just a pinch every couple days.
I feed 'tropical' spirulina 1mm pellets...fish pretty much pick them from my fingers, other then the blenny, he is jerk and bites me.
I also feed 'tropical' marine power LPS pellets, fish and bristle worms go crazy for them, everyone bites me when this goes in the tank..
I also will feed 1/8 of a cube of frozen mysis once a week, again everyone bites me for this too..

The fish get a tiny pinch of each pellet daily, the pellets are gone before any hit the sand...the reef roids goes in once or twice a week, and the mysis just on sundays...

My bigger concern is that my fresh made saltwater has higher po4 than the tank.

 

[outssider]

I have used the hanna phosphorus checker on my ro/di water. It's been a while but i believe it was very low..... but not zero.....I also checked tap water and it was much higher around 30-40ppb as i recall.....I have read on here that that checker is for salt water only. I would call hanna for an answer on that.....

 

[Vinny Kreyling]

Some ICP tests do RO water
Stay AWAY from ICP-Analysis from Coral Vue.
Too many problems there & I still can't register a month later.

 

[NanoReefWanabe]

Some ICP tests do RO water
Stay AWAY from ICP-Analysis from Coral Vue.
Too many problems there & I still can't register a month later.

Thanks will keep that in mind, wont be till the new year....my concern is the sample will freeze in shipping, and I dont know if that will effect it

 

[waqas_01]

Hey a fellow Ontarion...hehe.

As mentioned above, Hanna mentions their test kit is supposed to be used with saltwater. I tested it by trying to dilute my sample with rodi vs freshly made saltwater (fritz red box). The saltwater dilution reads almost double (100ppb vs 170ppb)....I'm battling high phosphates too.

Mind you the fresh saltwater alone I tested showed zero ppb, so I know the change is just the way the reagent reacts with rodi vs saltwater.

A few things:
- the hanna testers are super sensitive to debris floating in your sample
- feed the bare minimum...I've cut it down to one salifert spoon (the teeny tiny ones) per day of PE or NLS pellets and I've started to see a downward trend. Any less than this and I started to see a real change in aggression amongst the fish (2 clowns and a yellow coris wrasse...just starting out with stocking)
- test your nitrates as well to make sure you aren't bottomed out there and preventing phosphate uptake with your export method
- lastly if you're really high on phosphates they could be leaching from your rocks so keep that in mind amongst the other culprits

 

[LesMartin]

Try back to back tests with the Hanna to see how consistent it is. Many users report wildly inconsistent readings so that may be the root of your 'problem'.