phosphate questions

[Dan_P]

I’ve been testing phosphate once before my lights are on and then once when my lights turn off. Nothing more than that so I don’t have a real curve. All I know is that it measures 0.1 in the morning right before lights on and then 0.00-0.02 at night when the lights turn off.

Thanks. Your observations are interesting.

If, as @Lasse suggests that bacteria, or maybe more broadly speaking, non-photosynthetic or heterotrophic life works more or less around the clock, one output being phosphate, then when photosynthetic life kicks in and starts growing, one outcome would be the uptake of phosphate. And if the phosphate demand of the phototrophs exceeds that produced by heterotrophs, phosphate disappears during the day.

A very interesting possibility here is that monitoring the interplay of heterotrophic and phototrophic life via hourly phosphate levels might be a diagnostic of aquarium health. In general, I find these dynamic observations much more informative than single point in time measurements.

 

[Lasse]

The ph swing tightened up. Before running at night it had a 0.4 swing. Now it swings tighter at 0.2 swing. I’m happier with it now between 8.15 and 8,35. Before the alk change it swung from 8.00 to 8.45.

I saw the movie - no doubt what is causing your PO4 consumption IMO. Such a dense population of corals will surly consume a lot of P by photosynthesis.

Thanks. Your observations are interesting.

If, as @Lasse suggests that bacteria, or maybe more broadly speaking, non-photosynthetic or heterotrophic life works more or less around the clock, one output being phosphate, then when photosynthetic life kicks in and starts growing, one outcome would be the uptake of phosphate. And if the phosphate demand of the phototrophs exceeds that produced by heterotrophs, phosphate disappears during the day.

A very interesting possibility here is that monitoring the interplay of heterotrophic and phototrophic life via hourly phosphate levels might be a diagnostic of aquarium health. In general, I find these dynamic observations much more informative than single point in time measurements.

The problem with this is how to monitor a swing around 0.02 to 0.07 ppm with equipment that have an accuracy of plus minus 0,02 ppm. I think I have solve that problem - I have developed a method with Hanna HI-774 that make it possible to make at least 11 individual measures on the same reagent and sample. I have one valve that is the zero - 1 valve (or in my present investigation - 2 valves that I prepare with reagent, mix for 2 minutes and stand for 3 minutes. I use the zero up to C2, change to sample and read with a short press on the button (no 3 minutes) - next step - zero with the zero sample - at C2 change and read the prepared sample again (on short press on the button) and so on up to 11 times. I note the results - take away one of the lowest readings and one of the highest and calculate the average figure. I will describe that method more later on when I have tested it for some days. I use that method just now in order to analyse my PO4 concentration every 4 hour and it looks like I can see this daily swing in at least my aquarium. I´ll come back with more results later on.

Sincerely Lasse

 

[Randy Holmes-Farley]

R

Randy I have been testing my phosphates at different times and yes I am noticing this in my tank. Right before the lights go on I am getting 0.1 ppm. When the lights turn off I am at 0.2-3 ppm. What would you expect the phosphate levels to do during a 24 hour photo period. In addition I would expect the nitrate levels to fluctuate in the same manner. Not sure how this phosphate sink works here though. Would that keep phosphate at a constant if the rocks are not saturated? I believe my rocks must be saturated cause I’ve never run binders.

the rocks do not saturate at levels of P thst reefers maintain. They can take on more and more as the water column concentration rises.

I’m not really sure I see reasons for any particular time dependence to exist. How long does it take for fish to excrete phosphate from foods they eat? And obviously food dosing patterns vary. And feces may continue to release phosphate over time. What time would nocturnal creatures release most P? What about filter feeders?
I’m interested to see detailed measurements, but I’d expect it to vary a lot tank to tank and wouldn’t have expected much day to night change due to rock and sand buffering of P levels.

 

[Lasse]

the rocks do not saturate at levels of P thst reefers maintain. They can take on more and more as the water column concentration rises.

I’m not really sure I see reasons for any particular time dependence to exist. How long does it take for fish to excrete phosphate from foods they eat? And obviously food dosing patterns vary. And feces may continue to release phosphate over time. What time would nocturnal creatures release most P? What about filter feeders?
I’m interested to see detailed measurements, but I’d expect it to vary a lot tank to tank and wouldn’t have expected much day to night change due to rock and sand buffering of P levels.

The inorganic orthophosphate will not come directly from feces or organic matter. The organic P content of feces and other organic matters must be mineralised into inorganic orthophosphate and that´s mostly a bacteria task (fungus and some other microorganisms can be active in this process too). This process is 7/24. From my ecological and biological point of view I can see many reasons why you will read time depended left over of inorganic orthophosphate in a closed system with photosynthesis. With Hanna we analyse inorganic P - either as PO4 or PO4-P. Depended of Hanna model. Free Inorganic PO4 = orthophosphate.

However - can you prove that in a reef aquarium with hobby tests? I´m not sure but I have an interesting test ongoing. The problem for me is that I have a light reversed refuge and therefore consumption of orthophosphate even during night time for the DT. The test should be done on a tank with dense growth of corals and with a 12 - 12 light cycle for the whole system.

I´ll comeback

Sincerely Lasse

 

[epsteino]

the rocks do not saturate at levels of P thst reefers maintain. They can take on more and more as the water column concentration rises.

I’m not really sure I see reasons for any particular time dependence to exist. How long does it take for fish to excrete phosphate from foods they eat? And obviously food dosing patterns vary. And feces may continue to release phosphate over time. What time would nocturnal creatures release most P? What about filter feeders?
I’m interested to see detailed measurements, but I’d expect it to vary a lot tank to tank and wouldn’t have expected much day to night change due to rock and sand buffering of P levels.

So what does that do to the P concentration in the water column? As the rock pulls in more P doe the concentration in the water column stay the same or rise ? Is the P covalently bonding to the rock or is it just ironically bonding?

 

[epsteino]

the rocks do not saturate at levels of P thst reefers maintain. They can take on more and more as the water column concentration rises.

I’m not really sure I see reasons for any particular time dependence to exist. How long does it take for fish to excrete phosphate from foods they eat? And obviously food dosing patterns vary. And feces may continue to release phosphate over time. What time would nocturnal creatures release most P? What about filter feeders?
I’m interested to see detailed measurements, but I’d expect it to vary a lot tank to tank and wouldn’t have expected much day to night change due to rock and sand buffering of P levels.

Sorry ionically

 

[epsteino]

I saw the movie - no doubt what is causing your PO4 consumption IMO. Such a dense population of corals will surly consume a lot of P by photosynthesis.


The problem with this is how to monitor a swing around 0.02 to 0.07 ppm with equipment that have an accuracy of plus minus 0,02 ppm. I think I have solve that problem - I have developed a method with Hanna HI-774 that make it possible to make at least 11 individual measures on the same reagent and sample. I have one valve that is the zero - 1 valve (or in my present investigation - 2 valves that I prepare with reagent, mix for 2 minutes and stand for 3 minutes. I use the zero up to C2, change to sample and read with a short press on the button (no 3 minutes) - next step - zero with the zero sample - at C2 change and read the prepared sample again (on short press on the button) and so on up to 11 times. I note the results - take away one of the lowest readings and one of the highest and calculate the average figure. I will describe that method more later on when I have tested it for some days. I use that method just now in order to analyse my PO4 concentration every 4 hour and it looks like I can see this daily swing in at least my aquarium. I´ll come back with more results later on.

Sincerely Lasse

Thank you. I understand what you are saying. Do you think i am having deadly low phosphate levels? Not sure. When the levels drop does the levels in the rocks replenish the P in the water?

What do you expect to see when leveled get too low?

 

[Randy Holmes-Farley]

The inorganic orthophosphate will not come directly from feces or organic matter. The organic P content of feces and other organic matters must be mineralised into inorganic orthophosphate and that´s mostly a bacteria task (fungus and some other microorganisms can be active in this process too). This process is 7/24. From my ecological and biological point of view I can see many reasons why you will read time depended left over of inorganic orthophosphate in a closed system with photosynthesis. With Hanna we analyse inorganic P - either as PO4 or PO4-P. Depended of Hanna model. Free Inorganic PO4 = orthophosphate.

However - can you prove that in a reef aquarium with hobby tests? I´m not sure but I have an interesting test ongoing. The problem for me is that I have a light reversed refuge and therefore consumption of orthophosphate even during night time for the DT. The test should be done on a tank with dense growth of corals and with a 12 - 12 light cycle for the whole system.

I´ll comeback

Sincerely Lasse

I disagree and the papers I have seen do not support that idea. Fish release waste phosphate (which is the majority of P they eat) in feces and through the gills. The phosphate in feces partly just leaches out, and some needs metabolic action to release it. What effect that all has on timing in a reef tank, I have no idea.

 

[epsteino]

the rocks do not saturate at levels of P thst reefers maintain. They can take on more and more as the water column concentration rises.

I’m not really sure I see reasons for any particular time dependence to exist. How long does it take for fish to excrete phosphate from foods they eat? And obviously food dosing patterns vary. And feces may continue to release phosphate over time. What time would nocturnal creatures release most P? What about filter feeders?
I’m interested to see detailed measurements, but I’d expect it to vary a lot tank to tank and wouldn’t have expected much day to night change due to rock and sand buffering of P levels.

So what you believe the phosphate levels in the tank are mostly due to Are feeding and pooping and when that occurs. I feed 2-3 times a day and usually target feed the corals with mostly Red Sea A and B during the last hour of light. Maybe that’s why my levels are higher in the morning before I turn on the lights? My heaviest feed is the last hour of light and it may take several hours to get processed and produce P?

 

[Randy Holmes-Farley]

So what you believe the phosphate levels in the tank are mostly due to Are feeding and pooping and when that occurs. I feed 2-3 times a day and usually target feed the corals with mostly Red Sea A and B during the last hour of light. Maybe that’s why my levels are higher in the morning before I turn on the lights? My heaviest feed is the last hour of light and it may take several hours to get processed and produce P?

Might be. The question is how long it takes phosphate to go from foods to animal to water. In a person it takes 2-10 hours. I do not know the timing of those effects in fish or corals or crabs or whatever is eating the food.

 

[Lasse]

I disagree and the papers I have seen do not support that idea. Fish release waste phosphate (which is the majority of P they eat) in feces and through the gills. The phosphate in feces partly just leaches out, and some needs metabolic action to release it. What effect that all has on timing in a reef tank, I have no idea.

I can agree that some orthophosphate can leach out from feces because feces is mainly a bacterial mess. however - never heard about a leakage of orthophosphate through the gills. I do not say you are wrong but I would like to see a reference of that in order to educate myself. NH3/NH4 will mainly be released by the gills in saltwater fish - but I have never heard about a significant PO4 release through the gills.

Most fish are constructed in a way that says eat and release poop as I know. The digestive channel is like a tube - however a long tube in some fish.

I feed my fish around 21:00 in the evening and rather much. In my present investigation I will skip the feeding this night and see whats happen.

Sincerely Lasse

 

[epsteino]

I can agree that some orthophosphate can leach out from feces because feces is mainly a bacterial mess. however - never heard about a leakage of orthophosphate through the gills. I do not say you are wrong but I would like to see a reference of that in order to educate myself. NH3/NH4 will mainly be released by the gills in saltwater fish - but I have never heard about a significant PO4 release through the gills.

Most fish are constructed in a way that says eat and release poop as I know. The digestive channel is like a tube - however a long tube in some fish.

I feed my fish around 21:00 in the evening and rather much. In my present investigation I will skip the feeding this night and see whats happen.

Sincerely Lasse

Lasse. How are the tests going?

 

[Lasse]

Its not easy. I had to work out a methode there Hannah's HI-774 accuracy of plus minus 0.02 does not play a major role. I do like this. I prepare 3 sample vial. 1 vial is the zero - the other two is my samples. Fill up with 10 ml test water en each vial. Take the zero, clean the outside thoroughly with a towel. Put it in the Checker. press two time till C2 comes up. Take sample 1 and put in the checker instead for the zero. Press once very short - the checker will analyse the first sample (without reagents) - should show up 0.00 - if not clean again till it show up 0.00 (using the same method - the zero - press twice - C2 show up and after that - put in sample 1 and a short press. When sample 1 shows the same (0.00) as the zero - I do the same with the vial containing sample 2. Now I put the zero away for a while and put in reagens in sample 1 and 2. Turn upside down in two minutes. Clean and put aside after 2 minutes. Put the zero sample in the checker, press two - till C2 shows - now press a long press till 3 minutes start to count down. After 3 minutes the checker will read the zero sample and it will show 0.00. With the zero sample in the checker press till yo se C2 again. Switch to sample 1 and a short press - the checker read the sample 1 - and you have the first result. Write it down. Do the same with sample two (but no 3 minutes) - put zero sample into the checker - press till C2 and switch to sample 2 - shor press and it read sample 2. Write down the figure. Put in zero sample - press till C2, switch to sample 1 - press short and you will get your second result. I have done this eleven times with each sample. After that I take away 1 lowest reading and 1 highest reading of each sample - leaving 9 samples to take an average of. Put together the average of both sample 1 and 2 and a new reading - this is my result!! It take around 10 minutes to analyse both samples this way with 11 individual readings against the zero sample. The question is if the colour will change during 10 minutes after the three minutes of developing. I have done trend lines off all my tests and - yes - it can change a little - but in both directions. The tendency is however much lower than the accuracy - so I think that I get a better precision with this method. Yes - when you do 11 test of the same sample after each other - you will note the plus minus 0.02 ppm very well. Som examples. It is ppm PO4 that have been measured

My goal was to do a complete test round every 4 hours. I did take automatic samples 00:00 and 4:00 but the result change too much during 4 and 8 hours prior the analyse - I had to take away these results. Below you will see the result between 20-03-02 and 20-03-05.

I have done nearly 75 test but I´m not satisfied with my methodology. I have seen that I normally have my highest reading around 12:00 and the lowest around 20:00. I will run another serie of test during maybe 5 - 7 days with sample times 08:00 and 20:00 on workdays and 08:00, 12:00 and 20:00 other days. I have done test the last 8 days but it is first the last 3 days I satisfied with part of the methodology. I have logged the result together with my pH. The result indicates lower readings in the end of the light period and at the top of the pH. For some people it maybe indicate a chemical reaction (bound and dissolving of calcium phosphate) and for some it maybe indicate an uptake by photosynthesis. Maybe are the truth something between. However - it can´t be seen in this diagramme below - test I have done at 12:00 looks to have the highest concentration of PO4 - but the pH is not lowest at that time.

I will be away from home for 10 days now so I have to wait with my test till the end of march and hope to come back with a better investigation. It looks like I have a general rise in PO4 too, therefor I will run a lower amount of GFO during my vacation.

​

Sincerely Lasse

 

[Dan_P]

Its not easy. I had to work out a methode there Hannah's HI-774 accuracy of plus minus 0.02 does not play a major role. I do like this. I prepare 3 sample vial. 1 vial is the zero - the other two is my samples. Fill up with 10 ml test water en each vial. Take the zero, clean the outside thoroughly with a towel. Put it in the Checker. press two time till C2 comes up. Take sample 1 and put in the checker instead for the zero. Press once very short - the checker will analyse the first sample (without reagents) - should show up 0.00 - if not clean again till it show up 0.00 (using the same method - the zero - press twice - C2 show up and after that - put in sample 1 and a short press. When sample 1 shows the same (0.00) as the zero - I do the same with the vial containing sample 2. Now I put the zero away for a while and put in reagens in sample 1 and 2. Turn upside down in two minutes. Clean and put aside after 2 minutes. Put the zero sample in the checker, press two - till C2 shows - now press a long press till 3 minutes start to count down. After 3 minutes the checker will read the zero sample and it will show 0.00. With the zero sample in the checker press till yo se C2 again. Switch to sample 1 and a short press - the checker read the sample 1 - and you have the first result. Write it down. Do the same with sample two (but no 3 minutes) - put zero sample into the checker - press till C2 and switch to sample 2 - shor press and it read sample 2. Write down the figure. Put in zero sample - press till C2, switch to sample 1 - press short and you will get your second result. I have done this eleven times with each sample. After that I take away 1 lowest reading and 1 highest reading of each sample - leaving 9 samples to take an average of. Put together the average of both sample 1 and 2 and a new reading - this is my result!! It take around 10 minutes to analyse both samples this way with 11 individual readings against the zero sample. The question is if the colour will change during 10 minutes after the three minutes of developing. I have done trend lines off all my tests and - yes - it can change a little - but in both directions. The tendency is however much lower than the accuracy - so I think that I get a better precision with this method. Yes - when you do 11 test of the same sample after each other - you will note the plus minus 0.02 ppm very well. Som examples. It is ppm PO4 that have been measured

My goal was to do a complete test round every 4 hours. I did take automatic samples 00:00 and 4:00 but the result change too much during 4 and 8 hours prior the analyse - I had to take away these results. Below you will see the result between 20-03-02 and 20-03-05.

I have done nearly 75 test but I´m not satisfied with my methodology. I have seen that I normally have my highest reading around 12:00 and the lowest around 20:00. I will run another serie of test during maybe 5 - 7 days with sample times 08:00 and 20:00 on workdays and 08:00, 12:00 and 20:00 other days. I have done test the last 8 days but it is first the last 3 days I satisfied with part of the methodology. I have logged the result together with my pH. The result indicates lower readings in the end of the light period and at the top of the pH. For some people it maybe indicate a chemical reaction (bound and dissolving of calcium phosphate) and for some it maybe indicate an uptake by photosynthesis. Maybe are the truth something between. However - it can´t be seen in this diagramme below - test I have done at 12:00 looks to have the highest concentration of PO4 - but the pH is not lowest at that time.

I will be away from home for 10 days now so I have to wait with my test till the end of march and hope to come back with a better investigation. It looks like I have a general rise in PO4 too, therefor I will run a lower amount of GFO during my vacation.

​

Sincerely Lasse

Thanks for the report. I will bring @Rick Mathew attention to your work. He has a similar interest in testing phosphate levels over time, but in sample containers. The size of variation in your readings seem to correspond to his, and if so, the trend you see might be on the edge of being statistically significant.

 

[Rick Mathew]

TRITON is my standard and corresponds very well to how my corals thrive.

My Hanna - HI - 774 - show 0.07 - 0.1. Cyano and no growth. TRITON show 0.02. Rise my to 0.12 (HI-774) TRITON show 0.04. After a couple of weeks - growth very good and Cyano on the defensive.

Sincerely Lasse

Lasse: Some really nice and interesting work. It will take me a while to digest it...Thanks for sharing it

With regard to the PO4 test with the checkers and TRITON:

Actually I don't question the TRITON results...What I question is the stability of the sample taken for shipments to be tested...

Here is a link to some work I have done on samples storage with regard to PO4 stability...Bottom line is when a tank sample is stored the measure PO4 levels decrease over time when measured by a HI-736 or HI-774...Which is an indicator that by the time a sample reaches the ICP vendor the measured PO4 will be lower--- Much Like you report above.

https://www.reef2reef.com/threads/s...on-phosphate-measurement.696800/#post-7171250

 

[Rick Mathew]

Thanks. Your observations are interesting.

If, as @Lasse suggests that bacteria, or maybe more broadly speaking, non-photosynthetic or heterotrophic life works more or less around the clock, one output being phosphate, then when photosynthetic life kicks in and starts growing, one outcome would be the uptake of phosphate. And if the phosphate demand of the phototrophs exceeds that produced by heterotrophs, phosphate disappears during the day.

A very interesting possibility here is that monitoring the interplay of heterotrophic and phototrophic life via hourly phosphate levels might be a diagnostic of aquarium health. In general, I find these dynamic observations much more informative than single point in time measurements.

Very interesting thought Dan!

 

[Lasse]

Yes - for PO4 - its true. My loss was as below. But Triton analyse total P and I believe them that total P will not change. after the analyse they assume that all is in the form of PO4 and show that result. In my case - the low figures from Triton was in line with how my aquarium developed. It response quickly when I start to add PO4.

Sincerely Lasse

2020-03-03 08:00​	0 timmar	4 timmar	8 timmar
nummer	Prov 2
1​	0,15​	0,11​	0,08​
2​	0,14​	0,11​	0,08​
3​	0,15​	0,13​	0,08​
4​	0,13​	0,13​	0,08​
5​	0,15​	0,12​	0,07​
6​	0,14​	0,11​	0,07​
7​	0,14​	0,11​	0,06​
8​	0,14​	0,11​	0,07​
9​	0,15​	0,1​	0,07​
	1,290​	1,030​	0,660​
	0,143​	0,114​	0,073​
	Dif tot	-0,029​	-0,070​
2020-03-03 12:00​	0 timmar
nummer	Prov 2	4 tim
1​	0,21​	0,17​
2​	0,17​	0,15​
3​	0,17​	0,14​
4​	0,17​	0,16​
5​	0,17​	0,15​
6​	0,18​	0,15​
7​	0,17​	0,15​
8​	0,17​	0,13​
9​	0,17​	0,15​
	1,580​	1,350​
	0,176​	0,150​
	dif	-0,026​

 

[Lasse]

In my test I saw that in a serie of 11 tests with the same sample (the same reagent) a variation of in line with the accuracy (plus minus 0.02 ppm) The variation looks like it was mostly spontaneously and random. I did more than 20 x 2 tests that all more or less show the same pattern. I can read 0.05 ppm but do not really know if it is 0.03 or 0.07 ppm. let us say - the real result is 0.03 ppm - shown by Triton. But I randomly read 0.07 ppm on my HI-774. Not very surprising for me. I will never go back to the original way of using my HI-774. I will use 2 vials (one Zero - 1 sample) and read at least 5 times after each other. 10 if I get very unstable readings. I will use the average mostly but if one reading differ to much - I will not count that. During this more than 20*2*11 readings - I get "just happens" readings rather often - in a serie that shows 0.15 - 0.17 I suddenly could read 0.35 or 0.1. When this happens - the checker mostly did a long calibration in the next zero check. Hanna checker is great for us that can´t see colours very well but they are equipment that cost around $ 70 here in Sweden and we can´t expect the delivering results that´s difficult for $ xxxx equipment to deliver!

However - with this method - at least I rely on my results more. I´m sure that triton give the most accurate result because i have been working with checkers that constantly show a lower value compared with Triton and checkers - like mine that constantly shows higher values.

When I come home from my vacation - I will do test and see if it possible to valuate if - and how much - cronic error values a single checker show.

I will mix my sample with Al or Fe remover and after a while analyse the sample that contains most of my ions but no PO4. This way - I maybe can valuate if my water contain any interfering compounds.

Sincerely Lasse

 

[Dan_P]

In my test I saw that in a serie of 11 tests with the same sample (the same reagent) a variation of in line with the accuracy (plus minus 0.02 ppm) The variation looks like it was mostly spontaneously and random. I did more than 20 x 2 tests that all more or less show the same pattern. I can read 0.05 ppm but do not really know if it is 0.03 or 0.07 ppm. let us say - the real result is 0.03 ppm - shown by Triton. But I randomly read 0.07 ppm on my HI-774. Not very surprising for me. I will never go back to the original way of using my HI-774. I will use 2 vials (one Zero - 1 sample) and read at least 5 times after each other. 10 if I get very unstable readings. I will use the average mostly but if one reading differ to much - I will not count that. During this more than 20*2*11 readings - I get "just happens" readings rather often - in a serie that shows 0.15 - 0.17 I suddenly could read 0.35 or 0.1. When this happens - the checker mostly did a long calibration in the next zero check. Hanna checker is great for us that can´t see colours very well but they are equipment that cost around $ 70 here in Sweden and we can´t expect the delivering results that´s difficult for $ xxxx equipment to deliver!

However - with this method - at least I rely on my results more. I´m sure that triton give the most accurate result because i have been working with checkers that constantly show a lower value compared with Triton and checkers - like mine that constantly shows higher values.

When I come home from my vacation - I will do test and see if it possible to valuate if - and how much - cronic error values a single checker show.

I will mix my sample with Al or Fe remover and after a while analyse the sample that contains most of my ions but no PO4. This way - I maybe can valuate if my water contain any interfering compounds.

Sincerely Lasse

@Lasse and @Rick Mathew, have either of you seen any validation reports on Triton’s analytical methods that verifies that they can produce accurate and precise measurements? Or are we trusting them?

 

[Rick Mathew]

@Lasse and @Rick Mathew, have either of you seen any validation reports on Triton’s analytical methods that verifies that they can produce accurate and precise measurements? Or are we trusting them?

I have not...The only information I have ever seen is the article by Rich Ross & Dr Chris Maupin where they provided 3 individual samples of Certified Sea Water and had them tested and they did an accuracy and precision analysis on the results...Being as how this certified sample was most likely sterile it does not account for any Bio-activity that a tank water would have...none the less it is a data point.

Here is the link

Skeptical Reefkeeping 12: Triton Lab ICP-OES Testing of a Certified Artificial Saltwater Standard

From ReefsMagazine By Rich Ross and Dr. Chris Maupin At MACNA 25 in Denver, the potential for the new ICP-OES aquarium water testing by Triton Lab in Germany made many saltwater hobbyists swoon. Th…

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