Good Greef Posted June 1, 2018 Share Posted June 1, 2018 This hobby, while great, can often be overwhelming with anecdotal and empirical data. But sometimes I just wonder how/why things work the way they do, but don't have time or energy to ask "why" since the answer doesnt really matter. What random, even "stupid" questions have y'all wanted to know but never had time to ask? Here's a few of mine: Q. How do Hanna checkers actually measure the light? Does it measure whats going through the digital display? Should the single point light source ideally sit directly above the checker? Directly in front of the digital display? Q. When one has undetectable no3 and po4, but still has algae, the common response is that the nuisance algae consumes the nutrients before you can test for it. And that it also consumes it before your GFO or corals can absorb it. Have there been any experiments done that measure the rate of consumption of no3 and po4 that various mediums consume? It would be cool to see the rate differences b/w dinos, cyano, GHA vs. GEO, corals, etc. Quote Link to comment Share on other sites More sharing options...
jolt Posted June 1, 2018 Share Posted June 1, 2018 36 minutes ago, Good Greef said: This hobby, while great, can often be overwhelming with anecdotal and empirical data. But sometimes I just wonder how/why things work the way they do, but don't have time or energy to ask "why" since the answer doesnt really matter. What random, even "stupid" questions have y'all wanted to know but never had time to ask? Here's a few of mine: Q. How do Hanna checkers actually measure the light? Does it measure whats going through the digital display? Should the single point light source ideally sit directly above the checker? Directly in front of the digital display? On the Hannas there is an internal LED that is the light source as far as I know 2 Quote Link to comment Share on other sites More sharing options...
Good Greef Posted June 1, 2018 Author Share Posted June 1, 2018 On the Hannas there is an internal LED that is the light source as far as I knowThat makes too much sense. I always wondered how varying light levels, types, locations could provide a constant read. Quote Link to comment Share on other sites More sharing options...
Timfish Posted June 2, 2018 Share Posted June 2, 2018 I've wondered about algae growth with undetectable nitrates levels also. Especially puzzling was noticing years ago in my maintenance business was no correlation between detectable PO4 and NO3 and algae growth (see my two threads on hair/nuisance algae). One realization when I started digging through research papers was we need to think of in terms of total nitrogen* and total phosphate# available in a system and our test kits are incapable of testing most of the forms each of these can take. * Nitrogen can be available in our systems as Dissolved Organic Nitrogen (DON) which can be in the form of urea (fish poop) or amino acids, Dissolved Inorganic Nitrogen (DIN) which is ammonia/ammonium and/or nitrates (nitrites are also a form of DIN but the biology converts it so fast to nitrates or to ammonia/ammonium I stopped testing for it years ago). It can also be referred to as Dissolved Organic Matter, DOM. Nitrogen is also floating around our systems as Particulate Organic Nitrogen, PON, and as Particulate Organic Matter. # Phosphorous is also available in both Dissloved Organic (DOP) and Inorganic (DIP, orthophosphate, PO4) forms. As with nitrogen it is usually also included in the terms DOM as well as POM. 1 Quote Link to comment Share on other sites More sharing options...
+Dogfish Posted June 2, 2018 Share Posted June 2, 2018 1 hour ago, Timfish said: I've wondered about algae growth with undetectable nitrates levels also. Especially puzzling was noticing years ago in my maintenance business was no correlation between detectable PO4 and NO3 and algae growth (see my two threads on hair/nuisance algae). One realization when I started digging through research papers was we need to think of in terms of total nitrogen* and total phosphate# available in a system and our test kits are incapable of testing most of the forms each of these can take. * Nitrogen can be available in our systems as Dissolved Organic Nitrogen (DON) which can be in the form of urea (fish poop) or amino acids, Dissolved Inorganic Nitrogen (DIN) which is ammonia/ammonium and/or nitrates. It can also be referred to as Dissolved Organic Matter, DOM. Nitrogen is also floating around our systems as Particulate Organic Nitrogen, PON, and as Particulate Organic Matter. # Phosphorous is also available in both Dissloved Organic (DOP) and Inorganic (DIP, orthophosphate, PO4) forms. As with nitrogen it is usually also included in the terms DOM as well as POM. Im learning a bit more about this, reading a sea grass and other saltwater planted tanks threads Quote Link to comment Share on other sites More sharing options...
Bpb Posted June 5, 2018 Share Posted June 5, 2018 On 6/1/2018 at 1:47 PM, Good Greef said: On 6/1/2018 at 11:15 AM, jolt said: On the Hannas there is an internal LED that is the light source as far as I know That makes too much sense. I always wondered how varying light levels, types, locations could provide a constant read. Correct. If you run a test with no vial and leave the lid open, you'll see theres a green diode that flashes for a second at the end of the phos timer or pretty much right when you press the button on the alk checker (those are the two I own, i'd assume its the same for the rest). There is a photoreceptor oppsite the diode and it measures the green light attenuation based on the reaction in the tube and assigns a numerical value to it based on whatever function is programmed. Thus, your test result. Alot more consistent of a read than guessing a titration end point, or a color shift. In a blacked out tube the green light will be the same all the time and the device measures specific wavelengths. It won't be tricked like your own eyes. 1 Quote Link to comment Share on other sites More sharing options...
Good Greef Posted June 5, 2018 Author Share Posted June 5, 2018 Very helpful Timfish and Bob. I guess I coulda just ran my Hanna testers with the lid open and looked lol. But the explanation is so much better. 1 Quote Link to comment Share on other sites More sharing options...
victoly Posted June 5, 2018 Share Posted June 5, 2018 9 hours ago, Bpb said: Correct. If you run a test with no vial and leave the lid open, you'll see theres a green diode that flashes for a second at the end of the phos timer or pretty much right when you press the button on the alk checker (those are the two I own, i'd assume its the same for the rest). There is a photoreceptor oppsite the diode and it measures the green light attenuation based on the reaction in the tube and assigns a numerical value to it based on whatever function is programmed. Thus, your test result. Alot more consistent of a read than guessing a titration end point, or a color shift. In a blacked out tube the green light will be the same all the time and the device measures specific wavelengths. It won't be tricked like your own eyes. To piggyback, the best way to measure alkalinity (and in fact even the definition) relies on a titration, but instead of a color endpoint, it's a pH endpoint. The lab grade alkalinity tests add tiny increments of acid until a specific pH is reached at which all titratable bases, in our case we're primarily interested in the most prevalent carbonate in marine waters as bicarbonate (HCO3) have been consumed. Quote Link to comment Share on other sites More sharing options...
Bpb Posted June 5, 2018 Share Posted June 5, 2018 To piggyback, the best way to measure alkalinity (and in fact even the definition) relies on a titration, but instead of a color endpoint, it's a pH endpoint. The lab grade alkalinity tests add tiny increments of acid until a specific pH is reached at which all titratable bases, in our case we're primarily interested in the most prevalent carbonate in marine waters as bicarbonate (HCO3) have been consumed. Ph reduction test? Did I get the name right? Sent from my iPhone using Tapatalk Pro Quote Link to comment Share on other sites More sharing options...
victoly Posted June 5, 2018 Share Posted June 5, 2018 its french so its pronounced "pee-ahtch" 2 Quote Link to comment Share on other sites More sharing options...
Bpb Posted June 6, 2018 Share Posted June 6, 2018 What did you just call me!?!Sent from my iPhone using Tapatalk Pro 1 1 Quote Link to comment Share on other sites More sharing options...
victoly Posted June 6, 2018 Share Posted June 6, 2018 Entre dans la voiture. Nous allons au magasin! Quote Link to comment Share on other sites More sharing options...
Good Greef Posted June 24, 2018 Author Share Posted June 24, 2018 Another thing I'm hoping you chemistry majors can help with. Q. It's impossible to get 100% of phosphate reagent into the vial, using the Hanna ULR Po4 test. Suppose I get 90% of the reagent in there, how does that impact my result? Surely Hanna assumes ppl can't get it all there, even if I use a paper funnel. Quote Link to comment Share on other sites More sharing options...
Sierra Bravo Posted June 24, 2018 Share Posted June 24, 2018 Open and pour your reagent package as shown in this video. I've never had an issue getting all to nearly all the reagent into a vial. It also helps to thump/shake the envelope like you would a pack of sugar before cutting it open as well. 2 Quote Link to comment Share on other sites More sharing options...
Good Greef Posted June 27, 2018 Author Share Posted June 27, 2018 Makes it look so easy haha. I've been using a mini funnel made outta scrap paper. But sometimes when tapping it down, dust flings outward. I'll try tapping more ahead of time, to get them out of those corners. Quote Link to comment Share on other sites More sharing options...
Sascha D. Posted June 27, 2018 Share Posted June 27, 2018 On 6/5/2018 at 8:17 AM, Bpb said: Correct. If you run a test with no vial and leave the lid open, you'll see theres a green diode that flashes for a second at the end of the phos timer or pretty much right when you press the button on the alk checker (those are the two I own, i'd assume its the same for the rest). There is a photoreceptor oppsite the diode and it measures the green light attenuation based on the reaction in the tube and assigns a numerical value to it based on whatever function is programmed. Thus, your test result. Alot more consistent of a read than guessing a titration end point, or a color shift. In a blacked out tube the green light will be the same all the time and the device measures specific wavelengths. It won't be tricked like your own eyes. I hit the button once by accident and noticed that light coming on. My tester has a red diode. Do you think the color of light makes a difference? Quote Link to comment Share on other sites More sharing options...
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