Hannah checkers - how much do you trust/like them?

[madweazl]

I thought @Randy Holmes-Farley had commented on this issue before but I can't find it now.

I haven't noticed one but I haven't done any digging either.

 

[billw]

There's some technique involved, but I have no problem with mine. I have the alkalinity, calcium and ultra low phosphorus checker. I imagine most of the problems with the calcium checker occur in measuring the 0.1 ml required for the test. The kit comes with a 0.1 ml pipette now.

 

[PiscesPower]

I use the Alk & the Ca and have not had any issues. The first few I compared with Red Sea and got pretty close to the same readings.

 

[Forsaken77]

You have to read reviews on specific ones. Some are accurate, some aren't. And the ones that use the powder reagent are a pain. Because if you don't get every spec of powder in the small cuvette, how much does that throw off the test?

The dKh model is liquid, which is easy. The Ultra Low Range Phosphorus is better than the Phosphate, but you need to do the conversion to change the results into Phosphate instead of Phosphorus. (Take the reading, multiply by 3.066, then divide by 1,000)

 

[BlennyKravitz]

I used Red Sea for everything and still do except I switched to the Hanna Alk ppm and the ULR phosphorus. They are faster and easier to use and I trust them. Because it's so fast I check alk daily and phosphate Saturday and Wednesday.

For the powder packet I fold into a triangle and rip along the dotted line then unfold so it looks like this picture. Most everything 99% goes into the cuvette with a little tapping in the packet.

I keep a small folded piece of wax paper handy and just cut the Hanna pack open and dump the whole thing out. It slides out easily and you are certain to get it all in the cuvette.

 

[Bob Escher]

I use the Hanna DKH checker and love it for everything else I use Red Sea and Aqua forest for calcium

 

[Hanna Instruments]

Hanna has to say this because they sell to everyone – people with functional RODI filters who maintain their units AND people who never change their filters and have "RODI water". If you have 0 TDS RODI water it should be fine....I never used distilled and (once I practiced) had no problem matching my test results to Salifert.

Distilled water is less of a question mark in terms of quality variability. Since almost nobody makes their own distilled that means it's less likely to be screwed up – it's all "professionally made".

One important thing to note is TDS is actually the least refine measurement for water purity.

A TDS meter is used to determine the amount of dissolved particles in the water, usually in parts-per-million or ppm. However this is not necessarily true. TDS meters are actually measuring EC or electrical conductivity.

EC is the measurement of how well a medium (usually water) conducts electricity. In general conductivity increases as the concentration of ionic dissolved solids increases. Using EC as a measure of TDS is non-specific for ion type. An ion is a charged particle present in the solution that contributes to the current flow. Conductivity measurements are used for additional units such as TDS and salinity. EC is commonly expressed as micro Siemens/per cenitmeter (μS/cm) or milli-Siemens/per centimeter (mS/cm). Units may be converted as:

1000 μS/cm = 1.0 mS/cm.

Most EC/TDS meters use percent (%) of the full scale (f.s.) to determine accuracy. This becomes very important in relation to low conductivity water where values as close to zero are preferred. Range is used to describe the minimum or maximum detection limits for that particular meter. Range is thus used in determining the accuracy of TDS meters. For example, a common accuracy statement for many EC/TDS meters is ± 2% f.s., with a range of 999 ppm TDS. In this scenario, the measure of uncertainty is 2 percent of 999 ppm.

0.02 X 999 ppm = 19.98 ppm

This would means your results could be ±20 ppm different then the results displayed. So if your meter was reading 30ppm the results could actually be from 10 ppm to 50 ppm.

Conductivity/TDS meters come in a variety of price points ranging in quality, accuracy and applications. If you are using a TDS meter for RODI water to be used in a reef tank, then you want a meter designed for low range conductivity. A goal of most reef keepers is to have source water as close to 0 ppm total dissolved solids as possible. Many hobbyists use their TDS meter to determine when it’s time to change their RODI cartridges. If your TDS meter has a range of 1000 ppm or more, then you can expect your results to never be more accurate than ±20 ppm, assuming a 2% f.s. accuracy statement.

For spot-checking your system we recommend the HI98308 Pure Water Tester. This handheld meter is temperature compensated, has a maximum detection limit of 99.9 µS/cm (approx. 50ppm TDS), accuracy of ±2% f.s., and can be manually calibrated with 84 µS/cm buffer. This meter can be used for checking your reservoir or by taking a sample directly from your RODI output. When using the Pure Water Tester, a reading of 20.0 µS/cm would equate to 10ppm TDS, and your measure of uncertainty would be from 19.6 µS/cm to 20.4 µS/cm.

I bring this up because the HI758 Calcium Checker does need pure deionized water in order to function within its accuracy statement.

 

[Hanna Instruments]

I have had very good results with the Hanna Checkers. I use the Alk, Phosphorous and Calcium. On occasion I have used the Nitrite checker. I found the key is good lab practices and I can get repeatable and accurate results when compared to outside testing services

Just a note on the Hanna Calcium Checker. I have had very good success with this checker and have been using it for over 2 years. I made three changes that brought my Gage repeatability and reproducibility to less than 10% of the target range (100...350-450)

1) Purchased .3mL syringe...very accurate...You can find these from multiple suppliers

2) Use Hanna Deionized water (HI70436) and not my RODI water which has a small amount of calcium in it and is variable from batch to batch.

With the dilution ratio being so high and the water sample amount being so small these two changes took my R&R (repeatability and reproducibility) from between 30-40% (not good! almost random results) to less than 10% a very acceptable range for this test. My results have been validated by external testing sources so I feel confident in the measurement.

3) After the test is complete I rinse the vial and cap with the Hanna deionized water then fill the vial to the top with this water and store it this way until next use. Then on the next use I empty the vial do a quick rinse with the deionized water and proceed with the test.

IMO with good laboratory practices these checkers are great tools and do not rely on color change interpretation to make the measurement which in itself is a variable

Great explanation and good laboratory practices, thank you for being a valued Hanna customer!

 

[Kyl]

I was turned onto these by someone on this board: https://www.amazon.com/gp/product/B009CZEQ36/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
they fit right into the cuvette and it so much easier not to spill the reagent.

Oh man, I have got to find a northern source-able equivalent for that!

 

[Tiggy13]

The Hanna Alk tester is a reliable must have for an SPS tank! I use mine at least twice a week & I love it!

 

[rosshamsandwich]

Whether they work or not, the customer service is non-existent. I've repeatedly tried to contact them regarding issues/concerns and no callback, no followup, and no one picks up the phone...

 

[rosshamsandwich]

The Hanna ALK/dKH Checker and the ULR Phosphorus Checker are, as far as I am concerned, not just better than others but REQUIRED basic equipment for anyone with an SPS system.

I used my dKH Checker nearly every single day! Quick, cheap refills, easy, and spot on results EVERY time.

Get them.

why do you need to use it every single day??? you can't figure out how to make your tank stable?

 

[Hanna Instruments]

Whether they work or not, the customer service is non-existent. I've repeatedly tried to contact them regarding issues/concerns and no callback, no followup, and no one picks up the phone...

What country are you located in? For the United States we can be reached at 401-765-7500 Monday - Friday 8:30am-5pm EST or by email at [email protected]

 

[rosshamsandwich]

I'm in the United States. The Phosphate checker throws readings all over the place. I fill two vials, follow all the instructions, wait 3 minutes, make sure there's no bubbles. One reading is 0.26 ppm, next reading 0.20 ppm, then 0.10 , then 0.12, then 0.15, then 0.21, then 0.13.. What is up with that? This thing was $50 dollars, for Christ's sake.

When I perform the same methods on the Alk checker, I consistently get the same number. But the phosphate checker is ridiculous.

 

[rosshamsandwich]

Got a automatic Reply from "Tim Larson" Out of office until September 11th. Just my luck. Thanks, Hanna Checkers...

 

[zachxlutz]

why do you need to use it every single day??? you can't figure out how to make your tank stable?

Alk is commonly tested daily by many successful reef keepers. A change in alk consumption points to many possible situations that testing daily will give you the jump on.

 

[PAXpress]

Kind of the same as a lot have said. I use the Hanna Alk and have the Hanna Phosphorus but rarely use it. The alk saves me so much time and seems to be very accurate. I dont like the phosphorus because of those stupid packets and the timeout the checker has. Use red sea for everything else.

 

[rosshamsandwich]

Alk is commonly tested daily by many successful reef keepers. A change in alk consumption points to many possible situations that testing daily will give you the jump on.

Why not get a calcium reactor and test while you are dialing it in, then set it and forget it?

 

[Hanna Instruments]

I'm in the United States. The Phosphate checker throws readings all over the place. I fill two vials, follow all the instructions, wait 3 minutes, make sure there's no bubbles. One reading is 0.26 ppm, next reading 0.20 ppm, then 0.10 , then 0.12, then 0.15, then 0.21, then 0.13.. What is up with that? This thing was $50 dollars, for Christ's sake.

When I perform the same methods on the Alk checker, I consistently get the same number. But the phosphate checker is ridiculous.

For most accurate results you need to use one vial as there can be differences in the glass which could cause variations in how light penetrates the cuvette.

Also the HI713 low range phosphate Checker has a measure of uncertainty of ±0.04 ppm ±4% of reading @ 25°C/77°F. If your results are 0.20 your variations can be from 0.16 to 0.24 ppm

The numbers you just presented were those taken consecutively from the tank or was water allowed to sit outside of the aquarium prior to analysis? What was the timing variation on those tests?

Make sure to follow our 8 Checker Best Practices Blog for best results.

Before you turn on the phosphate meter you must open your reagents and prepare your cuvettes. The meter does have a relativity short auto-shut-off feature. This is to prevent over mixing of reagent which could cause inaccurate results. The chemical reaction has a very specific timing and gently mixing for 2 minutes will be sufficient to dissolve powder. Make sure you are using the built in 3 minute timer by holding down the button at C1 phase.

For lower range phosphate levels, like yours, its best to use the HI736 ULR Phosphorus Checker. Both Checkers are measuring orthophosphates.

Conversion Table
http://hannainst.com/resources/aqua...phate-conversion-table--hanna-instruments.pdf

HI713 vs HI736
http://hannainst.com/resources/aqua...ates-in-your-reef-tank--hanna-instruments.pdf

 

[Hanna Instruments]

Got a automatic Reply from "Tim Larson" Out of office until September 11th. Just my luck. Thanks, Hanna Checkers...

Other Hanna employees have received your email and will respond shortly. That is a technical error in our system.