difficulty discerning shade of blue in Salfert phosphate test

[Ballyhoo]

which Hannah measurement would I accept when the from the same sample of water three are different?

 

[RockRash]

which Hannah measurement would I accept when the from the same sample of water three are different?

Just average them out.

 

[NanoNana]

that is exactly how i do salifert though. drop by drop until it turns red/orange - per instructions

What Salifert test are you using for PO4 that you count drops? Salifert PO4 is 4 drops of reagent A and 1 scoop of reagent B. At least mine is.
I count drops for mag, calcium, KH, PH but not PO4. And PO4 turns blue, not orange.
Salifert PO4 is not a titration test. Are you maybe following directions for the wrong test?

Have LFS test for you. According to Hannah your PO4 is 0.5 and Slaifert is 0.05. That’s a lot of discrepancy. Test at the same time each day because levels in the tank can fluctuate a lot.

If it’s actually 0.5, up your nutrient export or feed less or don’t worry about 0.5 which is what I do.
Chasing PO4 which is measured in one hundredths of parts is gonna drive you crazy.
You had low nutrients, added fish to bump them. They bumped now you’re trying to lower them. Your tank is going to have these fluxes because it’s young. As many water changes as you’ve been doing if your PO4 is 0.5 you are either overstocked or over feeding.
It’s a common thing that happens. You try to correct low numbers and over correct and end up high. Let the tank mature. Correct levels when they get close to being dangerous. Make SMALL changes, a tiny bit less food, if feeding 3x a day try halving the mid day feeding. If this helps after a couple weeks but not enough, feed even less. You can’t fix it in a day.

If your LFS and ICP come back at 0.0 anything, assume you got a faulty Hannah tester and have whomever you bought it from replace it. If that one reads high it’s user error.

Hannah has the reputation it has because it is notoriously reliable. It’s also a hand held computer that can be damaged or have issues on rare occasions.

Why don’t you just set up real time testing with probes. Not being rude but money isn’t an issue for you. If it were for me I’d be automated.

 

[Glowurm]

What Salifert test are you using for PO4 that you count drops? Salifert PO4 is 4 drops of reagent A and 1 scoop of reagent B. At least mine is.
I count drops for mag, calcium, KH, PH but not PO4. And PO4 turns blue, not orange.
Salifert PO4 is not a titration test. Are you maybe following directions for the wrong test?

Looks more like he has confused the Calcium and Mag with the Phosphate test.

 

[NanoNana]

Looks more like he has confused the Calcium and Mag with the Phosphate test.

He’s showing us a blue vial so I’m thinking is just confusing them in the explanation but yeah. That my thought.

 

[Ballyhoo]

He’s showing us a blue vial so I’m thinking is just confusing them in the explanation but yeah. That my thought.

yea, the phos tes you add a second reagent and measure color change. so maybe that does not qualify as titration, but mag, calcium and KH /Al would.

hanna is all over the place. maybe it's from when I dropped a vile I do not see any visual defect but I dropped a vile once. Maybe there's some defect in the vile that's causing changes and measurements. But there's no consistent measurements in hAnna. In Sal is consistent. incidentally, I should be receiving my ICP results shortly. Although doesn't seem like many people take much stock in those.
also, with the ICP test, they test phosphorus and phosphate. Are people saying that phosphates degrade overtime ie the phosphate molecules degrades into something else?

 

[Randy Holmes-Farley]

yea, the phos tes you add a second reagent and measure color change. so maybe that does not qualify as titration, but mag, calcium and KH /Al would.

hanna is all over the place. maybe it's from when I dropped a vile I do not see any visual defect but I dropped a vile once. Maybe there's some defect in the vile that's causing changes and measurements. But there's no consistent measurements in hAnna. In Sal is consistent. incidentally, I should be receiving my ICP results shortly. Although doesn't seem like many people take much stock in those.
also, with the ICP test, they test phosphorus and phosphate. Are people saying that phosphates degrade overtime ie the phosphate molecules degrades into something else?

Correct, phosphate is not a titration, while calcium, magnesium and alk are typically titrations.

Phosphate by icp can be problematic at low levels because organisms such as algae may take it up and then stick to the bikes or get removed before testing. Some companies add chemicals to prevent growth. Some do not.

 

[piranhaman00]

There are only two Hannah checkers you must have, one being phosphate/phosphorus.

The other being copper

 

[Jimbo327]

I trust Hanna for phosphorus/phosphates and nitrates because frankly color match sucks. More error on the interpretation of color. I have the hanna copper and alk as well. Maybe if I was 10 years younger, my eye sight might lead to less error.

I trust Salifert on the titration based tests like alk, cal, mg.

 

[Ballyhoo]

also, my KH/Alk measured at at nine. Is that too high?

 

[Randy Holmes-Farley]

also, my KH/Alk measured at at nine. Is that too high?

It’s fine. I recommend 7-11 dKH.

 

[Ballyhoo]

i brought my Hanna tester to my LFS they tested my water with mine at .33 and with their hanna it came out to .32. i'm maybe doing something wrong in the testing but idk what. anyways i did a 30 percent water change after that.
i wonder if that level of phosphate is damaging to coral.

 

[GARRIGA]

You test as I do with API. Been doing it that way since the 80s. When in doubt. I pick the worse closest color and call it a day. It's hobby grade therefore already inaccurate. Other than copper dosing. Can't think of anything else where NASA level precision a must. Day I have to skate 0.3 ppm the day I go get another gold fish. Hopefully this one out lasts my first. Bought before lunch. Dead before dinner

 

[Pod_01]

i wonder if that level of phosphate is damaging to coral.

Hmmm….

What do you think?

 

[NanoNana]

Hmmm….

What do you think?

No. There are many ppl who run with phosphates at 1.0 without issue. Super high PO4 long term can cause browning or dull colorations but 0.3 is not. It’s fine to keep an eye on it and you’ll start to notice I did this and this happened, fed this and this happened etc. Young tanks are inherently unstable which is why they move from one ugly phase to another. As the ecosystem stabilizes , the levels will stabilize. At that point you can make meaningful corrections.

 

[Ballyhoo]

so should i continue aggressive water changes or no? if i was at .33 then big water change maybe just regular water change since others are doing well at that level.

 

[Pod_01]

so should i continue aggressive water changes or no? if i was at .33 then big water change maybe just regular water change since others are doing well at that level.

Water changes don’t really impact PO4, they work well on NO3. PO4 is usually bound to the rocks/ sand and stays at equilibrium with water. The rock and sand acts like a reservoir. If you add more to water column some will bind to the surfaces and new equilibrium is reached. If the water column concentration drops PO4 will unbind from the surface and new reduced value will be reached. So you need to do lot of water changes to move the needle down. I would just monitor and see where PO4 goes.

When measuring PO4 I tend to measure before feeding or late at night long after feeding to get consistent measurements. You don’t want to measure the PO4 that was artificially high due to feeding.

Good luck,

 

[PotatoPig]

i really do not understand what you are saying : that viewing a sample of salifert titration from an angle increases the reading ten fold?

Yep. Have the card vertical and look through the cup from the side. You’re looking through 10x as much liquid so the color is 10x deeper, find the one that most closely matches and then divide by 10. Somewhere in the test instructions they tell you this as a method to get test sensitivity down in the lower ranges.

See below for the same instructions from their nitrate test:

Also, I don’t know if there’s something weird going on with your lighting that’s making the camera show the test darker than it is, but in the photos you show the result looks more like somewhere between 0.25 and 0.5, somewhat consistent with the Hanna results.

 

[Ballyhoo]

those images are probably fairly well representing the test coloration.
it's just that a few weeks ago I had dosed phosphate because the Sal test had showed zero phosphates so someone told me to sparingly dose phosphate and I thought I was overdosing and been changing water due to overdose phosphate. One time by accident I dosed phosphatase instead of micro bacter7 a whole cap full, which would be like 10 mL. The bottles look similar. It's the same brand.