My Hanna phosphate checker is trolling me.

[Coelli]

Tested a couple of weeks ago (11/28) after not testing for a few weeks and got .11. Yikes! Tested again with a fresh battery and got 0.00. Phew! Changed out GFO just in case.

Tested this morning and got .29. Holy smokes. Tested again and got .27. This makes NO sense; with phos that high wouldn't my SPS be in really bad shape? Thinking maybe it was the water I store the vials in I flushed the vial and cap with fresh RODI and tested the tank water again. 0.00. Tested the vial storage water. 0.00. I'm keeping Hanna in business with reagents.

At this point I'm not sure what to believe (but I'll probably bring my water to the LFS for testing or pick up a different test kit).

I have 0 detectable nitrates and no nuisance algae other than a little bryopsis. It takes days for film algae to develop on the glass. My SPS is hit or miss on PE; most stylos/birdsnest/digitata are fluffy, wild valida and joe the coral are fully extended, garf bonsai has visible if not fluffy polyps, etc., and only fussy ORA Tri-colored Valida is looking tan, everything else has good color. Anemones, gorgs, LPS look great.

Alk 9.3
Calcium 450
Mag 1290

How frustrating to not know if I'm at Defcon 5 or not. For now do I believe my eyes or the .2x readings? At ~.28 what would I be seeing in the tank?

[bertoni]

People have varying reports on the effects of phosphate on stony corals. For that matter, the meter or reagents might be having a problem, but it sound more like a problem with the storage of the vials. I would trust my eyes more than any test kit, in any case.

[jason2459]

Could be reagent but sounds more like inconsistency in testing procedures. Are you rinsing the vial and device used to fill the vial up with tank water first? Are you getting all the reagent out consistently (nothing caked or stuck in a crease)? Making sure there's no bubbles or marks on the sides of the vial? Putting the vial in facing the same way each time? Using only 1 vial for testing? Mixing enough to have the reagent dissolve? Giving enough settling time?

[Coelli]

Could be reagent but sounds more like inconsistency in testing procedures. Are you rinsing the vial and device used to fill the vial up with tank water first? Are you getting all the reagent out consistently (nothing caked or stuck in a crease)? Making sure there's no bubbles or marks on the sides of the vial? Putting the vial in facing the same way each time? Using only 1 vial for testing? Mixing enough to have the reagent dissolve? Giving enough settling time?

Yes, I was very particular about all of it. I always cut the packets open and spread them wide enough to get all of the powder out. I have a small funnel that I cut the tip off of that I can sit on the top of the vial and I always tap it to make sure all of it went in. I use one vial and if I accidentally forget and press the button instead of holding it (I do this way too often) I start over. The reagents are still good and are from a new box purchased earlier this year. It's the darndest thing.

[jason2459]

Possibly reagents. Wouldn't be the first time.

[jason2459]

Is this the 713 I assume? You could get the calibration set as a reference for accuracy.

[Coelli]

Is this the 713 I assume? You could get the calibration set as a reference for accuracy.

Yes, it's the 713. The box of reagents had an exp date of 4/17. I'm about to start a new box with 6/17 date.

At this point I'm disregarding the 0.00 readings and assuming that the high readings are accurate. I dug around in my sump and found a little hair algae in my MarinePure rack, and it's the first hair algae I've ever seen in the year since the tank was filled. The fuge light has been running 24/7 (I ran out of outlets on my EB8 and don't have a spare timer), I've started adding Acropower and feeding more in the past couple of weeks. I also over-feed mysis because of my mandarin and inverts. So there are potential causes.

I changed out my GFO for Rowaphos yesterday and this morning the checker said 0.09. Getting the calibration kit seems like a good move. :) Thanks for reminding me there is one!

The phosphate could also be leaching out of some old rock I just added to the new 30g that was plumbed into the same sump a couple of days ago. The rock is live, but it had been sitting in a 10g tank with a HOB filter, a bunch of chaeto, and no water changes for about 8 months. I'm leaving the lights off in the new tank for now until everything's under control again. No sense in running them over an empty-except-for-rock tank and having to deal with algae there. The cleanup crew and blenny can handle anything in the main DT. I'm cutting back on feeding again too. So hard to find a balance that makes everyone happy. :)

[jason2459]

Just an FYI, you can't actually calibrate the Hanna checker it would be better labeled as a Reference kit. The 736 vials are sealed and read to go in the Reference kit. The 713 vials are not. One of them you have to uncap, add the reagent and recap it.

[newtank]

Noticed on mine that the lid started to not completely seal shut after a lot of use. I always ensure that the lid is sealed and I use my hands to completely cover the seam to ensure that zero light gets in. I also will get about 4 to 6 readings ,listing them in a spreadsheet to obtain an average. I noticed that readings stabilize within the margin of error, then I deem them reliable. FWIW

[Coelli]

Noticed on mine that the lid started to not completely seal shut after a lot of use. I always ensure that the lid is sealed and I use my hands to completely cover the seam to ensure that zero light gets in. I also will get about 4 to 6 readings ,listing them in a spreadsheet to obtain an average. I noticed that readings stabilize within the margin of error, then I deem them reliable. FWIW

Yep, I've noticed the same thing with the lid on mine and always double-check.

Yesterday I tested the water coming out of my reactor - .12 - and the tank water - .08. Go figure. Replaced the media with the last of my Rowaphos and will be switching back to GFO, just got another pound from Amazon. I still haven't cross-checked with another test kit but will pick up a Red Sea or Salifert later today.

[jason2459]

I'd look at the Elos Pro PO4 or Nyos as a fairly accurate alternative or to check against. Both get fairly high resolution. I found the Elos Pro easier to read the end points and better resolution.

Comparison review of different PO4 kits.
http://www.reefcentral.com/forums/showthread.php?t=2540702

[Coelli]

I'd look at the Elos Pro PO4 or Nyos as a fairly accurate alternative or to check against. Both get fairly high resolution. I found the Elos Pro easier to read the end points and better resolution.

Comparison review of different PO4 kits.
http://www.reefcentral.com/forums/showthread.php?t=2540702

Cool, thanks for the info!

[Scorpius]

You have to be super ocd/perfectionist to get a repeatable test result with the Hanna Checkers. All of them. :lol: It's a sensitive piece of equipment. :)

[jason2459]

You have to be super ocd/perfectionist to get a repeatable test result with the Hanna Checkers. All of them. [emoji38] It's a sensitive piece of equipment. :)
That's me with all my test kits.

[zachfishman]

Noticed on mine that the lid started to not completely seal shut after a lot of use.

Ours do this. I turn the cuvette about 90 degrees, try again, and repeat until the lid closes nicely.

[zachfishman]

Are you rinsing the vial and device used to fill the vial up with tank water first? Are you getting all the reagent out consistently (nothing caked or stuck in a crease)? Making sure there's no bubbles or marks on the sides of the vial? Putting the vial in facing the same way each time? Using only 1 vial for testing? Mixing enough to have the reagent dissolve? Giving enough settling time?

+1 get yourself a pack of Kimwipes (http://www.amazon.com/Kimberly-Clark-Kimtech-Kimwipes-Delicate-Disposable/dp/B00RORBXA8/ref=sr_1_1?ie=UTF8&qid=1450114522&sr=8-1&keywords=kimwipes) to keep the cuvette fingerprint-free. Once I start the procedure my bare hands don't touch the cuvette.

ALSO: I've found it very important to invert the cuvette back and forth for a FULL MINUTE to fully dissolve the reagent. I do this at the start of the 3:00 countdown.

[Scorpius]

+1 get yourself a pack of Kimwipes (http://www.amazon.com/Kimberly-Clark-Kimtech-Kimwipes-Delicate-Disposable/dp/B00RORBXA8/ref=sr_1_1?ie=UTF8&qid=1450114522&sr=8-1&keywords=kimwipes) to keep the cuvette fingerprint-free. Once I start the procedure my bare hands don't touch the cuvette.

ALSO: I've found it very important to invert the cuvette back and forth for a FULL MINUTE to fully dissolve the reagent. I do this at the start of the 3:00 countdown.

You're supposed to do this for two minutes per the instructions.

[jason2459]

copy paste on what I do and applies to the 713 and 736

736 manual
http://shop.hannainst.com/downloads/dl/file/id/1069/ist736_13_05_10.pdf

713 manual
http://shop.hannainst.com/downloads/dl/file/id/1053/ist713_03_13.pdf

I always make sure the do the same steps every single time and have always gotten consistent results. Others have had bad reagents in the past but I haven't had the problem yet but it's always a possibility with any test kit.




I have a pretty good routine down with this checker and do the same with the 713 checker as well. Always handing with a lint free cloth and never touch with fingers though all steps.




1. rinse out the vial with tank water several times and inspect vial for any blemishes.

2. Fill that vial with 10ml of tank water taking care not to have any bubbles on the sides (if filtered can skip step 4.)

3. Get a packet out and flick it a few times to loosen up the powder and move away from the area I'm going to cut in a curved pattern as indicated on the packet (I was doing this before they put that indicator on there as well)

4. Set the vial down with tank water and wait at least minutes doing other stuff ( I used filter out the sample with a coffee filter but this seems just as good and I'm usually doing several things at the same time)

5. Turn the checker on and wait for it to ask for C1

6. Place the vial in with the 10ml mark facing me

7. Cut open the reagent packet and pinch it open so the bottom part is creased to help funnel the powder out into the vial

8. Press the button to read C1

9. As soon as it asks for C2 I pull the vial out (never touching with my fingers at any stage of this using a lint free cloth) and add the reagent

10. Close the vial up and look at the time and gently start mixing the reagent into the water. Taking care not to form bubbles on the insides of the glass. Alternating between slowly inverting and gently swirling

11. As soon as the time changes on the 2 minute mark I press and hold the button to get the 3 minute timer.

12. Continue to gently mix the reagent for 30 more seconds inspecting for any bubbles on the sides or accidental blemishes

13. Place the vial back into the checker and wait for the count down.

14. Rinse immediately after getting the reading.




I find that the reagent for the ULR 736 checker dissolves a lot better then the 713 Low Range checker. Also the end result value is displayed a lot longer on my 736 ULR checker.