Getting 0.00 on Hanna HI713 Phosphate tester

[numin8r]

I am following the directions but the timeout on the hanna Phosphate checker is 2 minutes and it says to shake for 2 mins. If I shake for the full 2 mins it turns off. I read that you should use the same vial for the test. I only shake for a minute and put the covet in the tester and it says 0.00 after 3 minutes.

Are my phosphates really 0? I am dosing NP Bacto Balance (Carbon) but I stopped 2 days ago as I was getting some cyano on the sand bed.

Would the Phosphate ULR tester be better for me?

 

[Idech]

Do you first put the vial when it says C1, wait until C2 appears, do your 2 minute shaking and then put it back in ?

 

[numin8r]

Do you first put the vial when it says C1, wait until C2 appears, do your 2 minute shaking and then put it back in ?

Correct. I press the button wait for it to say c1. Add vial of 10mL of tank water. Wait for c2. Put reagent in vial and shake for around 1 min or close to 2 mins. The checker turns off after 2 mins. It takes me a bit to put the reagent inside the vial so the clock is ticking. Wait 3 mins and get 0.00

 

[Idech]

Correct. I press the button wait for it to say c1. Add vial of 10mL of tank water. Wait for c2. Put reagent in vial and shake for around 1 min or close to 2 mins. The checker turns off after 2 mins. It takes me a bit to put the reagent inside the vial so the clock is ticking. Wait 3 mins and get 0.00

It sounds like a defective unit. I have 2 Hanna checkers and none shut off at 2 minutes.

Can you return it ?

 

[Dburr1014]

It sounds like a defective unit. I have 2 Hanna checkers and none shut off at 2 minutes.

Can you return it ?

Didn't they have an issue with the timers? I thought they all got resolved but maybe they missed one.

 

[Idech]

Didn't they have an issue with the timers? I thought they all got resolved but maybe they missed one.

Oh, I didn’t know about that.

 

[Dburr1014]

Oh, I didn’t know about that.

Yes, the problem was when you shake it for 2 minutes the timer was going off and you put it back in and it would shut off. Exactly like he's describing. But all that was going on before I actually bought one so I don't remember if it was a phosphate tester.

OP, I guess contact Hannah directly and they should point you in the right direction. They have pretty good customer service, you probably have to send the unit in.

 

[topjimmy]

It was, because mine did it.

 

[DDenny]

I have two vials for this very reason but mine doesn’t time out after 2 minutes

 

[RelaxingWithTheReef]

I purchased one of the first HI736 Phosphorus Ultra Low Range testers.

The instructions are to shake for 2 min, and the Auto shut-off time is 3 minutes. This is a challenge because to get accurate results, the cuvettes need to be really clean. I would be cleaning away, and bang, the egg would shut off…

In their latest product manual dated 2/22, the Auto shut-off time was changes to 10 minutes.

You can try changing the battery, and cleaning the battery contacts in the tester. You could be having a power issue.

It’s possible the phosphate in your tank did crash, and that would not be a good thing. The HI713 has an accuracy of +-0.040 ppm, so even if the tester works, it’s somewhat unclear exactly what’s going on. Hanna offers more sensitive / accurate testers in their ULR product line.

HI713 Phosphate tester
Range 0.00 to 2.50 ppm as Phosphate
Resolution 0.010 ppm
Accuracy ±0.040 ppm ±4% of reading @ 25 °C (77 °F)

HI774 Ultra Low Range Phosphate
Range 0.00 to 0.90 ppm
Resolution 0.010 ppm
Accuracy ±0.020 ppm ±5% of reading @ 25 °C (77 °F)

HI736 Phosphorus Ultra Low Range
Range 0 to 200 ppb (as P)
Resolution 1 ppb
Accuracy ±5 ppb ±5% of reading @ 25 °C (77 °F)

Note - ppb Phosphorus can be converted to ppm Phosphate by multiplying by 0.003066.
HI736 then becomes:
Range 0 to 0.613 ppm as Phosphate
Resolution 0.003 ppm
Accuracy ±0.015 ppm ±5% of reading @ 25 °C (77 °F)

 

[numin8r]

I took my tank water to a fish store and they checked it and phosphate was 0. I also bought a salifert kit and also got 0. Is my tank really zero? I was watching this BRS video and there would be times when phosphate isn’t detected.

I was getting some kind of algae in spots on my sand and the rocks definitely have something funky going on. Some sps corals are not doing so well. Monti is covered with algae and some faded acros. I did put nori in tank and put reefroids 5 hours before testing and results still 0

BRS VIDEO

 

[Randy Holmes-Farley]

If you are getting undetectable phosphate and corals do not look well, feeding more or dosing phosphate are both appropriate things to try.