Water Testing Kit

[Levin Tilghman]

Can anyone recommend a good water testing kit?

 

[anewbie]

The 'standard' is api liquid test kit; i find them a pain and imprecise but better solutions are way more expensive. Possible european have found a better solution.

 

[MacZ]

There is no real recommendation ror a brand in my opinion.

If you are past the beginner stage, strip tests reading NO2, NO3, GH, KH and pH, with additional drips for pH, NO2 and NH3/4 you're all set.

If you're one of these chemistry geeks, forgo on the hobbyist test kits and look for lab standard tests on Ebay or Amazon.

And for the softwater experts it's strips and a TDS/EC meter. If something happens it will be either too quick to react anyway or obvious from the behaviour of the fish and there will be time.

 

[Ben Rhau]

Your mileage may vary, but for softwater tanks I very infrequently need to test water chemistry beyond regularly using a TDS/EC meter.

GH and KH I only need to do once, so that I know how my tap water breaks down (or not at all if I use RO).

NH3/4, NO2, NO3 I only need if the tank is overstocked. For example, if I have more fish than expected in a quarantine tank. But in those cases, I'm doing a lot of water changes anyway. In an understocked, heavily planted tank, the nitrogen will always be very low.

pH I don't need because I know my tanks start off slightly acidic and get more acidic over time with plants. It's useful in the beginning to understand if a strong base has been added to the tap water. Or, if you're intentionally lowering the pH with strong acid.

Dissolved oxygen I don't believe can be measured accurately with a drip test.

Free chlorine is useful if you're using RODI and not adding dechlorinator to the water. But you only need to do it at the beginning and then again if the RO membrane or DI resin are very old.

Granted, it took some testing to realize that I no longer need to test. The brand I use is also API.

Cheers

 

[dw1305]

Hi all,
What the others have said.

It really depends how much you want to spend, and semi-titrimetric methods, (drop tests) are generally better than strips, but I wouldn't base decisions based on their results.

The only "test kit" I use is conductivity meter, they are plug and play and even cheap meters are accurate.

Cheers Darrel

 

[Levin Tilghman]

There is no real recommendation ror a brand in my opinion.

If you are past the beginner stage, strip tests reading NO2, NO3, GH, KH and pH, with additional drips for pH, NO2 and NH3/4 you're all set.

If you're one of these chemistry geeks, forgo on the hobbyist test kits and look for lab standard tests on Ebay or Amazon.

And for the softwater experts it's strips and a TDS/EC meter. If something happens it will be either too quick to react anyway or obvious from the behaviour of the fish and there will be time.

Thanks!

 

[anewbie]

To be honest i think ph is pointless; so the only thing i measure routinely (once every 6 or so months) is the nitrate level on my large community aquariums to make sure it doesn't creep up. I do use an ec meter occasionally on my blackwater aquariums just to ensure relatively stability. I'm not sure why anyone would measure ph but i am a newbiew. I do have 2 tap water aquarium and when i move i measure gh kh (though it is not clear if i will move again or if there is a plant melt down in case tap water changed).

I never bother with test strip - my complaint with API is the measure of nitrate is not very accurate esp between 1 and 8 which is the general range that concerns me.

 

[dw1305]

Hi all,

I never bother with test strip - my complaint with API is the measure of nitrate is not very accurate esp between 1 and 8 which is the general range that concerns me.

It was actually the difficulties in nitrate (NO3-) testing that started me down the route to the <"Duckweed Index">.

Because all nitrate compounds are soluble, you <"need to reduce the NO3- to nitrite"> (NO2-) and then combine that NO2- with another reagent to produce a coloured compound that you can measure colorimetrically.

......... Nitrate (NO3-) is reduced to nitrite (NO2-) by vanadium chloride. The total nitrite ions are then reacted with sulphanilamide and N-1-naphthylethylenediamine dihydrochloride under acidic conditions to form a pink azo-dye......

You can get around this by using a <"nitrate ion selective electrode">, but they are big money.

When I found about the <"leaf color chart (designed for Rice growers)"> it allowed me to quantify "greeness" and then use it as a measure of <"fixed nitrogen availability">.

cheers Darrel

 

[anewbie]

Hi all,

It was actually the difficulties in nitrate (NO3-) testing that started me down the route to the <"Duckweed Index">.

Because all nitrate compounds are soluble, you <"need to reduce the NO3- to nitrite"> (NO2-) and then combine that NO2- with another reagent to produce a coloured compound that you can measure colorimetrically.

You can get around this by using a <"nitrate ion selective electrode">, but they are big money.

When I found about the <"leaf color chart (designed for Rice growers)"> it allowed me to quantify "greeness" and then use it as a measure of <"fixed nitrogen availability">.

cheers Darrel

But what does the duckweed index tell you? I mean it might tell you things are good but what does good mean? I don't believe it tells you if it is zero; and if we decide that as a sliding scale above zero is not good does it tell you it is better than not green but is it better than 50 or 40 (i.,e, how high can it be to still be 'good' by the duckweed index) ? And yes i might be displaying full ignorance by asking this question in this manner.

 

[MacZ]

Good means no or minimal signs of deficiencies. No unusually melting leaves, no discolourations. Also average growth.
Just keep in mind the index is a minimal dosage system. So you dial in from the low end, while other systems dial in from a rather random average or from the top, going down with dosage until reaching equilibrium.

 

[dw1305]

Hi all,

I don't believe it tells you if it is zero; and if we decide that as a sliding scale above zero is not good does it tell you it is better than not green but is it better than 50 or 40 (i.,e, how high can it be to still be 'good' by the duckweed index) ?

You can "dial in" <"leaf colour"> (and growth rate) to any nutrient dosing regime. Like @MacZ says I try and just keep the <"plants in slow growth">, but other people use much heavier nutrient additions.

I went away from Common Duckweed (Lemna minor) because it doesn't do well in very soft, low nutrient water and looks yellow whatever happens.

Amazon Frogbit <"(Limnobium (Hydrocharis) laevigatum)"> is now my preferred "duckweed" because it will persist at very low nutrient levels.

If you've got time all the details are in <"What is the Duckweed Index all about?">.

cheers Darrel

 

[anewbie]

Good means no or minimal signs of deficiencies. No unusually melting leaves, no discolourations. Also average growth.
Just keep in mind the index is a minimal dosage system. So you dial in from the low end, while other systems dial in from a rather random average or from the top, going down with dosage until reaching equilibrium.

Well in my case i'm looking for nitrate build-up from large fishes in large aquariums. This is very different than say a breeding tank with apisto where the load is extremely light and the water changes are quite large (at least in my case); i'm not sure the leaf colour is going to tell me if nitrate has jumped to 300.

 

[MacZ]

Well in my case i'm looking for nitrate build-up from large fishes in large aquariums. This is very different than say a breeding tank with apisto where the load is extremely light and the water changes are quite large (at least in my case); i'm not sure the leaf colour is going to tell me if nitrate has jumped to 300.

I basically just answered your question what's the purpose and principle of the duckweed index.

In that case I think something emersed is probably better. I know for example that Epipremnum is able to shoot up to 3 new leaves a day (!), if nitrates are higher than 100mg/l, but still grows 1 every two days if nitrates are between 10 and 25mg/l. Thus I always recommended such plants to put on rift lake tanks like Malawi tanks, so they would suck up most of the excess. Sometimes that made doing only one waterchange a week even possible in the first place, when without the plants 2 would have been the minimum. But that does not mean you get around testing. In your case checking the baseline with a driptest regularly (like once a month) and weekly checks with test strips are probably the least labourous and expensive option.

 

[anewbie]

I basically just answered your question what's the purpose and principle of the duckweed index.

In that case I think something emersed is probably better. I know for example that Epipremnum is able to shoot up to 3 new leaves a day (!), if nitrates are higher than 100mg/l, but still grows 1 every two days if nitrates are between 10 and 25mg/l. Thus I always recommended such plants to put on rift lake tanks like Malawi tanks, so they would suck up most of the excess. Sometimes that made doing only one waterchange a week even possible in the first place, when without the plants 2 would have been the minimum. But that does not mean you get around testing. In your case checking the baseline with a driptest regularly (like once a month) and weekly checks with test strips are probably the least labourous and expensive option.

so with my nitrate being below 5 (which is the actual case); that explains why my pothos is growing so slowly

 

[MacZ]

That's probably the case, yes.

 

[anewbie]

That's probably the case, yes.

So i need 30 more clown loaches At least they don't fitght too much.

 

[dw1305]

Hi all,

Well in my case i'm looking for nitrate build-up from large fishes in large aquariums.

You may find that test kits are a viable option, purely because you may have a lot more NO3- to measure. You would need to use serial dilution to give you a more accurate reading, basically carry on diluting the water to be tested, and then multiply the value of a colour (that reads in the middle of the colour chart) by the dilution factor. That is one of the reasons why reported nitrate values are often much lower than the real value, the colour chart doesn't differentiate between 30 and 300 ppm.

i'm not sure the leaf colour is going to tell me if nitrate has jumped to 300.

It won't give you an exact number, but Limnobium laevigatum has a very plastic response to nutrients and <"you will get triffid"> if you add enough nutrients.

and this is an aquarium plant.
<"https://www.ukaps.org/forum/threads...d-to-the-leaf-colour-chart.62129/#post-711133">.

You can still use plants as nutrient reducers in polluted situations. There is a large volume of scientific research using, mainly, Water Hyacinth (Eichornia crassipes) and Water Lettuce (Pistia stratiotes) to clean up sewage etc.

This one is open access "Unlocking the potential of Eichhornia crassipes for wastewater treatment: phytoremediation of aquatic pollutants, a strategy for advancing Sustainable Development Goal-06 clean water" <"https://link.springer.com/article/10.1007/s11356-024-33698-9">.

The reason that Eichornia is the preferred option in tropical situations is that it is a <turned up to eleven"> plant, it needs plenty of light, nutrient and warmth. It won't grow without these, which makes it less useful to us.

cheers Darrel

 

[dw1305]

Hi all,

In that case I think something emersed is probably better. I know for example that Epipremnum is able to shoot up to 3 new leaves a day (!), if nitrates are higher than 100mg/l, but still grows 1 every two days if nitrates are between 10 and 25mg/l. Thus I always recommended such plants to put on rift lake tanks like Malawi tanks, so they would suck up most of the excess.

The original version of the <"Duckweed Index"> used <"a rooted emergent plant">, because of this access to aerial gases.

The reason for a floating plant is purely convenience. They may not be <"quite as good"> as an emergent plant, but they are much more <"plug and play">.

cheers Darrel

 

[anewbie]

Hi all,

You may find that test kits are a viable option, purely because you may have a lot more NO3- to measure. You would need to use serial dilution to give you a more accurate reading, basically carry on diluting the water to be tested, and then multiply the value of a colour (that reads in the middle of the colour chart) by the dilution factor. That is one of the reasons why reported nitrate values are often much lower than the real value, the chart doesn't differentiate between 30 and 300 ppm.

It won't give you an exact number, but Limnobium laevigatum has a very plastic response to nutrients and <"you will get triffid"> if you add enough nutrients.

and this is an aquarium plant.
<"https://www.ukaps.org/forum/threads...d-to-the-leaf-colour-chart.62129/#post-711133">.

You can still use plants as nutrient reducers in polluted situations. There is a large volume of scientific research using, mainly, Water Hyacinth (Eichornia crassipes) and Water Lettuce (Pistia stratiotes) to clean up sewage etc.

This one is open access "Unlocking the potential of Eichhornia crassipes for wastewater treatment: phytoremediation of aquatic pollutants, a strategy for advancing Sustainable Development Goal-06 clean water" <"https://link.springer.com/article/10.1007/s11356-024-33698-9">.

The reason that Eichornia is the preferred option in tropical situations is that it is a <turned up to eleven"> plant, it needs plenty of light, nutrient and warmth. It won't grow without these, which makes it less useful to us.

cheers Darrel

So i grow a lot of frogbit; but to be honest in the tank where it grows tallest and darkest green the ntirate is just about 0; it was a scarecely populated (10 young green neon tetra) in a 20 long. I did add some nutrients that was nitrate and phosphate free - so i'm not sure i fully understand the mechanics here - this is the aquarium:

It doesn't show the top but the the plant pushed itself out of the water and (i presume) changed in some fashion for those leaves not actually on water. While this tank did have nutrients it clearly did not have much if any nitrate (the water was ro water).

 

[dw1305]

Hi all,

but to be honest in the tank where it grows tallest and darkest green the ntirate is just about 0

Perfect, I'm going to tell you that you have more fixed nitrogen then you have measured.

Why (and how) can I say this? It is because the plants can't <"lie"> and

it grows tallest and darkest green

tells me that fixed nitrogen isn't the <"limiting nutrient"> for plant growth.

The <"leaf colour chart"> has to work as a "measure" of available nitrogen. If it didn't? A <"lot of Rice"> (and Maize) growers would have gone broke.

"Assessment of Leaf Color Chart Observations for Estimating Maize Chlorophyll Content by Analysis of Digital Photographs" - <"https://acsess.onlinelibrary.wiley.com/doi/10.2134/agronj2015.0258">

cheers Darrel