Should I get the Phosphurous Checker?

[theokie]

Should I be getting the Hanna Phosphorus Checker? Now that I'm using LaCl more regularly, on a doser, my Phosphate checker consistently reads 0ppm. Is it worth it to get the Phosphorus Checker that will read down to ppb? Or should I just alter my dose so that I can get a detectable reading on my current checker and just adjust my maintenance dose around so that it reads 1ppm just so I know that I'm not over doing it?

This is for my SPS system, I've recently started to move all of my LPS out of it and about 80% have been moved over to the new LPS system. As I'm attempting to see if I will have better success by no longer trying to balance a mixed reef.

[asylumdown]

My 2 cents is that the phosphorous checked isn't worth the plastic it's made from. Unless you're using analytical lab methods (which include regularly washing your cuvettes in hydrochloric acid), its results are no more reliable than looking out your window and trying to guess the days temperature.

You're way better off looking at cues your tank is giving you, such as the rate film algae grows to get a sense of what's going on with phosphate in your system

[Jordon]

I really like mine. I rather not wait until A;age takes hold if i'm doing regular testing anyways. Knowing its on its way up via the checker before a visual cue is much better IMO.

I recommend it.

[tytown]

Just started measuring with Hanna ULR unit but have trouble getting the same reading twice. I've almost gone through a pack of reagent performing multiple measurements between my fresh, mix, and tank water. For example, tank readings were 57, 107, 35 (0.17, 0.32, 0.10 ppm), so I'm pretty much calling BS on this unit unless I'm doing something completely wrong... It's supposed to accurate to +-5% of its range so that's +-10 PPb or 0.03 ppm.
Does anyone get consistent readings close to the units rated accuracy???

[gregzz4]

There's been a number of posts on this topic lately, but they're hard to find as the spelling between phosphate and phosphorus is all mixed up

I like my Hanna HI 713 phosphate tester, but it takes some getting used to

[Aquattro]

I love mine, wouldn't use anything else. Then again, I tell the temp by looking out the window :)

[asylumdown]

Just started measuring with Hanna ULR unit but have trouble getting the same reading twice. I've almost gone through a pack of reagent performing multiple measurements between my fresh, mix, and tank water. For example, tank readings were 57, 107, 35 (0.17, 0.32, 0.10 ppm), so I'm pretty much calling BS on this unit unless I'm doing something completely wrong... It's supposed to accurate to +-5% of its range so that's +-10 PPb or 0.03 ppm.
Does anyone get consistent readings close to the units rated accuracy???

nope. Never once. Thought it was me, then I looked in to it. Testing at that resolution outside of an analytical lab is about as accurate as guessing your level by throwing darts at chart.

To be consistent at that sensitivity, you'd need to be measuring the volume of your sample with a micro-pipette, using a fresh pipette every time you collected the sample. You'd also need to be getting the exact same amount of reagent out of the powder pillow every single time (which you never are). You'd also need to be washing your sample cuvette in hydrochloric acid every couple of tests, only ever rinsing the cuvette out in the purest of DI/distilled water, and doing dummy tests with DI/distilled water before each test, as tiny amounts of phosphate can bind to the glass.

You'd also need to be collecting your samples from the exact same spot, at the exact same time, after following the exact same routine. Even dipping your hand in to the water at the time you collect the sample could throw off the results enough to make the number meaningless.

It's why I prefer the regular PO4 kit. It's not as sensitive, and the numbers still need to be viewed as relative rather than absolutes, but at least it's more consistent from reading to reading and gives you a better sense of the actual trend in your tank. When one result is 0.10 and the next one 5 minutes later is 0.32, you have spent 15 minutes obtaining no useful information.

[Aquattro]

I use the regular unit, and for 4 years I consistently got 0ppm. Which was what I wanted to see. Good enough for me. I have an Elos kit, I can't tell if it's 0.01, 0.1, 42.8, etc. Might be my eyes :)

[asylumdown]

+1. I use the regular unit as well. It's the ULR unit that I think is better suited as a pez dispenser.

[Aquattro]

+1. I use the regular unit as well. It's the ULR unit that I think is better suited as a pez dispenser.

Nah. I've got a Batman pez dispenser, way better!

[Craigdillman]

I have the hanma one with ppb love it seems to get fairly constituent reading but mostly I use it to test before after after GFO so I know when to replace it test before WC and once a week I can see p04 rising and sometime I need to change out gfo between WC others not. Honestly I couldn't handle trying to read what color off hue blue was which so opted for it

Just my 2 cents

[Wheelman76]

I use the ULR phosphorous checker , works great and I can do two tests back to back and get very consistent results. Usually within 2 or 3 ppb. I think getting all of the powder out each time makes a big difference. I cut the edges of the packet off on two sides and then fold the packet into a V shape and pour. Seems to work well to get all of the powder out everytime.

[tytown]

Agree on the Elos PO4 kit, that thing is a total waste of money.
So Wheelman and Craig, what are some typical values your phosphorus checker reads? And what do you expect it to read when you test?
Running GFO I would hope to see 10 and below but going by their rated accuracy there's no way I guy can even rely on that.
Just trying to gauge peoples phosphates and their expected reading from their ULR phos checker....
Thanks for all the replys so far

[Craigdillman]

Well for example last week my reading was 0.06 and this week (water change week and GFO change time) it was 0.09 so it just started to rise

[lastlight]

i previously owned the regular tester and always got zero which i never believed. i certainly had algae which apparently IS possible with real zero readings lol. i now use the ULR and for a while i couldn't get back-to-back consistent readings.

now i do a few things that seemed to have made testing reliable and i now like the device:

- only use one of the glass containers. zero the unit and add reagent to same one. avoid differences in glass/scratches etc between containers.

- store ro/di in container between uses then rinse well before use

- made a decent paper funnel to ensure i can more accurately get all or almost all the reagent into the container

- always rotate the glass to the same orientation in the device

[mikellini]

This thread is making me feel better about getting the phosphate checker vs phosphorus. As it is, I think there's too much number-chasing going on in this hobby.

[lastlight]

This thread is making me feel better about getting the phosphate checker vs phosphorus. As it is, I think there's too much number-chasing going on in this hobby.

if you like zero readings i highly recommend the phosphate checker =)

[Aquattro]

if you like zero readings i highly recommend the phosphate checker =)

Agreed. As long as mine says 0, I don't worry about it.

[lastlight]

Agreed. As long as mine says 0, I don't worry about it.

you're running a sand bed right?

[Aquattro]

you're running a sand bed right?

gobyless, yes.

[Wheelman76]

Agree on the Elos PO4 kit, that thing is a total waste of money.

So Wheelman and Craig, what are some typical values your phosphorus checker reads? And what do you expect it to read when you test?

Running GFO I would hope to see 10 and below but going by their rated accuracy there's no way I guy can even rely on that.

Just trying to gauge peoples phosphates and their expected reading from their ULR phos checker....

Thanks for all the replys so far


I typically get a reading of 4ppb (0.01) to 10ppb (0.03) when I test. I usually change out my rowa phos every 4 weeks , but I recently decided to let it run for 6 weeks to see how high the po4 would climb. I tested and I got a reading of 20ppb (0.06) and then tested again right after with the same vile , rinsing in between with RO water and I got a reading of 21ppb (0.06) which seems pretty accurate to me.

I also agree that it's a good idea to only use the one vial for the test and just get the reagent in there quickly and have the packet open and ready to go. I also have the same side of the vial facing the front for the whole test ( steps C1 and C2) I just make sure the 10ml writing on the vial is facing the front. Is any of that necessary ? Who knows lol , but I get consistent results using this checker so that's how I continue to do it.

[Wheelman76]

I should have mentioned that I'm really carefull that I wipe all the fingerprints off the vial in between all the steps of the test. I'm not sure if that would lead to inconsistent readings that people are getting or not?

[lastlight]

yes i didn't mention that as i assumed everyone would be doing that already but for sure it makes a difference.

[mikellini]

if you like zero readings i highly recommend the phosphate checker =)

If you're doing it right, a zero reading is good enough. Even if it's actually 0.04 (which is possible with a zero reading), that's low enough. If I knew for a fact it was 0.04, I wouldn't try to chase numbers and lower it to 0.03. And as long as you have fish and are feeding enough, there will always be enough trace phosphorus in the water for hard corals.

My point is that if phosphates are a problem, it will read above 0, and if it doesn't and I'm having a problem, then phosphates aren't the problem.

[mikellini]

Wow there's gotta be a better way to say that haha

[Fishfriend]

I have a hanna phosphorous checker that I can sale you for $20. I am getting out of the hobbie.

[asylumdown]

Part of me wonders if it's the units themselves then, because people who can't seem to get consistent results never do, while the other camp never seems to have problems. I actually have training in analytical methods and have spent an unfortunate number of hours in a soil and water lab, and I still can't get mine to work properly.

I had a period where I thought my tank was melting down because every week I'd test 0.03-0.08 ppm higher than the week before - even with fresh GFO, and even while dosing lanthanum. Converted to ppm, I was reading in the 0.3 range.

Then i did a sequence of tests back to back in one sitting. The levels rose by 0.03 to 0.08 with each sequential test! the reading was predicted by the total number of tests I had run in that vial, not the level of phosphate in my tank.

I did the acid wash (which melted the max volume marker right off), then did a dummy test with distilled water and still got a reading of like 16 ppb or something.

I promptly drove to Wai's and bought a regular PO4 kit. That appears to have solved my phosphate problem, as my readings have been 0.00 ever since :)

[lastlight]

the Lastlight Checker Holder© is fully compatible with both Hanna models. comes complete with removable and washable funnel.

http://fishbrains.net/images/93/lego1.jpghttp://fishbrains.net/images/93/lego2.jpghttp://fishbrains.net/images/93/lego3.jpghttp://fishbrains.net/images/93/lego4.jpghttp://fishbrains.net/images/93/lego5.jpg

[asylumdown]

Brett, there are times when life gets busy and I get all distracted, and just for the tiniest moment I forget that you're my hero.

Then you remind me.

[tytown]

Ok, feeling better about it tonight. I went at it again but with the approach based on people's comments and some other research and was able to get a spread of readings within the units rated accuracy +-0.03 ppm (+-5% of range; range =200 PPb)
I perfectly prepped the reagent packet to ensure that it would all get in the vial before the test is even started
Grabbed water from the same location in the tank being careful not to get finger water in the sample.
I kept the orientation of the vial the same throughout all tests (10ml facing me)
And I used a fresh microfibre cloth and meticulously buffed the outside of the vial.
After all that it tells me I have 0.09 - 0.12 ppm PO4.
I would have liked to know which of the above had the largest influence on the results and I wonder what my readings would have been if the vial was flipped 180. Unfortunately I can't debunk the errors I went through becuase I only have 4 reagent packs left from my box of 25 bought just yesterday.
I'll use the current levels as a reference from here on out.
Thanks everyone.

[asylumdown]

If you have access to one, might be nice to test with one of the PO4 hanna's as well. The other thing I would find is that my ULR kit, when converted to ppm, seemed incapable of returning a result much below 0.08, while the regular kit would return 0.00.

If both the regular range and ULR kits agree that your PO4 is in the 0.09 to 0.12 range, then your method probably worked and you can have a higher degree of confidence in your results.

[lastlight]

The lowest reading I've gotten with mine is 0.02 but I've often got 0.04.

And thx Adam when can I expect your order? Kids are wondering how many more units they have to build tonight before I give them water and rest.

[MitchM]

I also use the ULR checker but I don't use it for accurate numbers, only trends.
I use a target of 10ppb though to adjust my Foz Down dosing.
I also take the appearance of the tank to tell me what's what.