False Reading From Hannah Checker or High PO4

[Randy Holmes-Farley Verified Community Expert]

I don’t think silicate is any issue, and I’d accept the Hanna value unless there was a different reason to suspect an issue.

 

[Davisc1293]

Thank you i suppose its time for some Water Changes

I don’t think silicate is any issue, and I’d accept the Hanna value unless there was a different reason to suspect an issue.

after running my skimmer and phosguard for 24 hours i would expect some decline but just tested at 4.9 im lost.

 

[Uncle99]

Thank you i suppose its time for some Water Changes

after running my skimmer and phosguard for 24 hours i would expect some decline but just tested at 4.9 im lost.

4.9ppm phosphate?
is that a typo?

 

[Davisc1293]

4.9ppm phosphate?
is that a typo?

yes that was a typo .49ppm but even after skimming heavy and running a lot of phosguard for 24hrs.

 

[Uncle99]

yes that was a typo .49ppm but even after skimming heavy and running a lot of phosguard for 24hrs.

I’d suspect test false reading of your Hanna.
Salifert versus Hanna should not have that much flux.
You expected around .1ppm, Salifert reports same. Go with that.
Sometimes test results send us chasing numbers.
If your tank looks good, leave it.
If you believe it’s the cause of something bad, get a second opinion on the level.

 

[Davisc1293]

I’d suspect test false reading of your Hanna.
Salifert versus Hanna should not have that much flux.
You expected around .1ppm, Salifert reports same. Go with that.
Sometimes test results send us chasing numbers.
If your tank looks good, leave it.

just to clear things up that salifert test in the photo is a silica test. I have a really hard time trying to read the salifert phosphate test so i never/rarely use it.

 

[Uncle99]

just to clear things up that salifert test in the photo is a silica test. I have a really hard time trying to read the salifert phosphate test so i never/rarely use it.

Got it.
The only Hanna phosphate checker that ever worked well for me was the UL Phosphorus in PPB.
2 years running very consistent.

 

[Uncle99]

just to clear things up that salifert test in the photo is a silica test. I have a really hard time trying to read the salifert phosphate test so i never/rarely use it.

I’d try that Salifert again if you still have it.
May (or may not) provide some insight, you should be able to see the colour of .3-.5ppm phosphate.
That should at least answer too the Hanna 4.9 result.

 

[Davisc1293]

This is the salifert phosphate high sensitivity test so the scale should be halved. But like i said i never use this test because i find i very hard to read and the hanna has allways been consistent

 

[gbroadbridge]

This is the salifert phosphate high sensitivity test so the scale should be halved. But like i said i never use this test because i find i very hard to read and the hanna has allways been consistent

Assuming 20ml, 8 drops and 2 scoops, that's close enough to the Hanna to not make a difference.

0.25 or 0.49 call it 0.38 if you like, just plan to get it down .

GFO will have no problem dropping that over a week or so.

 

[Davisc1293]

Assuming 20ml, 8 drops and 2 scoops, that's close enough to the Hanna to not make a difference.

0.25 or 0.49 call it 0.38 if you like, just plan to get it down .

GFO will have no problem dropping that over a week or so.

I dont have a reactor and have never used gfo i have used phosguard in the past which worked well with heavy skimming but overnight it hasn't made a difference. Its a small tank so ill do a 10% wc tomorrow to nudge it in the right direction and keep running fresh phosguard?

 

[gbroadbridge]

I dont have a reactor and have never used gfo i have used phosguard in the past which worked well with heavy skimming but overnight it hasn't made a difference. Its a small tank so ill do a 10% wc tomorrow to nudge it in the right direction and keep running fresh phosguard?

Phosguard works for me too (I alternate Phosguard/GFO), but I use it in a reactor squished between some filter floss.

Phosguard can leach Aluminium which GFO cleans up, and GFO leaches Barium which Phosguard cleans up. lol.

Put it somewhere with good flow where preferable the entire flow is forced through it.

Probably some phosphate has bound to Rock and substrate, so it may take a few changes of phosguard to get it down.

 

[Davisc1293]

Phosguard works for me too (I alternate Phosguard/GFO), but I use it in a reactor squished between some filter floss.

Phosguard can leach Aluminium which GFO cleans up, and GFO leaches Barium which Phosguard cleans up. lol.

Put it somewhere with good flow where preferable the entire flow is forced through it.

Probably some phosphate has bound to Rock and substrate, so it may take a few changes of phosguard to get it down.

Thanks for that info! im going to do some more research on gfo and continue with the phosguard in the mean time.

 

[Davisc1293]

i did test my rodi water after a 10% wc that seemed to have no effect on the tanks level. but did test 0

Mixed some new water last night and re tested this morning. and it tested .07. I'm not sure where the phosphate is coming from in my new water.

 

[piranhaman00]

Every Hanna checker should have sample water filtered through 0.2um syringe filter , I have very good results with Hanna checkers

 

[Randy Holmes-Farley Verified Community Expert]

Mixed some new water last night and re tested this morning. and it tested .07. I'm not sure where the phosphate is coming from in my new water.

0.07 ppm in top off and new salt water may be from escaping the RO/di, but it is not worth worrying about in most contexts. You add far more phosphate every day in feeding than this route provides.

 

[Davisc1293]

0.07 ppm in top off and new salt water may be from escaping the RO/di, but it is not worth worrying about in most contexts. You add far more phosphate every day in feeding than this route provides.

Thank you that certainly makes since but also makes we wonder if it has anything to do with why my tank being at .5 ppm

 

[Randy Holmes-Farley Verified Community Expert]

Thank you that certainly makes since but also makes we wonder if it has anything to do with why my tank being at .5 ppm

It is a minuscule contributor.

Aquarium Chemistry: Phosphate And Math: Yes You Need To Understand Both

Foods are by far the most important source of phosphate in most aquariums. In considering whether sources of phosphate other than foods are important, one must carefully look to the actual amounts involved to determine whether other sources are even worth trying to minimize.

reefs.com

Comparison of Food Sources of Phosphate to Other Sources​

What about other sources of phosphate, like the “crappy” RO/DI water containing 0.05 ppm phosphate? A similar analysis will show it equally unimportant relative to foods.

Let’s assume that the aquarist in question adds 1% of the total tank volume each day with RO/DI to replace evaporation. Simple math shows that the 0.05 ppm in the RO/DI becomes 0.0005 ppm added each day to the phosphate concentration in the aquarium. That dilution step is critical, taking a scary number like 0.05 ppm down to an almost meaningless 0.0005 ppm daily addition. Since that 0.0005 ppm is 40-600 times lower than the amount added each day in foods (Table 4), it does not seem worthy of the angst many aquarists put on such measurements. That said, tap water could have as much as 5 ppm phosphate, and that value could then become a dominating source of phosphate and would be quite problematic. Purifying tap water is important for this and many other reasons.

 

[Davisc1293]

Just an update, My Hannah checker does seem to be reading extremely high but was right on with the standards I just got in from Hannah. On july 2nd my hanna was reading .18 ppm this is the same day i took a sample to send to icp. which came back at .05 just for a third test i picked up a nyos kit which is not detecting any PO4.

 

[WVNed]

Try cleaning your vials in acid.
If the machine reads the standards right it has to be the vials or the reagents.
For me it was the vials.