Did I finally figure it out?
- Thread starter Scubajoe1
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Scubajoe1
New member
Myka
Reefing since '93
Keep in mind the Hanna ULR checker has a detection limit of 5 ppb.
Ya,this. ^
I think you're jumping the gun by only waiting 2 weeks between removing GFO and dosing PO4. I'd be waiting longer - especially considering the crazy amount of food you pour in there! [emoji14] How big is your tank?
IMO the sand and rocks are sucking some of it up so keep an eye on it. Eventually you should get a measurable reading and then it may get to the point where you have to run GFO or some other method to keep it in check. I have no idea how long that will take OR if this theory is correct.
Ya,this. ^
I think you're jumping the gun by only waiting 2 weeks between removing GFO and dosing PO4. I'd be waiting longer - especially considering the crazy amount of food you pour in there! [emoji14] How big is your tank?
Scubajoe1
New member
I think a lot of that is technique based and I usually take a couple measurements for confirmation. Made up a phosphorus standard the other day at 100 ppb and got 97 but only did one measurement then. regardless I am at least at 0.015 ppm even if it were off by 5 ppb which is much better than 0 ppb. Will follow it over a few days now and see what happens to it and the tank inhabitants.
Myka
Reefing since '93
With all due respect, do you understand what "detection limit" means?
Scubajoe1
New member
Yes with all due respect as a Ph.D. analytical chemist for over 20 years now "detection limit" has nothing to do with instrument precision. LOD and LOQ will be the lower limits one can detect. Instrument accuracy will be based on several factors some of with may be instrument based while others are due to errors that can be controlled. Do you actually work for Hanna and know exactly how they determined that +/- 5 ppm value? Also they state +/- 5% of the reading for accuracy as well. if you would like I will call them tomorrow and get more details unless you do in fact work for them.
Scubajoe1
New member
Also the EMC deviation of +/- 5 ppm is discussed by someone from Hanna in this post.
As to why they list two specs for accuracy I am not sure yet but will find out.
http://www.reefcentral.com/forums/showthread.php?t=1909272
As to why they list two specs for accuracy I am not sure yet but will find out.
http://www.reefcentral.com/forums/showthread.php?t=1909272
Scubajoe1
New member
Thanks. It took me a minute to figure out what an ARCO was. :jester:
Scubajoe1
New member
Just an update....measured the tank this morning and reading 9 ppb so it looks like the inorganic phosphate is hanging around unlike the organic phosphate. very slight decrease from 11 ppb last night. Could be measurement variation or could be real. Will continue to track it. SPS all look happy this morning.
Myka
Reefing since '93
Now that I'm on a laptop instead of Tapatalk, I can see that your tank is a 180-gallon. I don't think that food amount is too crazy. Good luck with the dosing - be careful or you'll have a thread like Wally B.
Well then, you should understand why your comment sounded totally ridiculous. :lolspin: Also, the phrase "with all due respect" loses all value when followed by insulting words. 
I said nothing insulting to you, and I'm not sure why you think it's ok to act the way you are? Maybe you're one of those geniuses with no social skills, but that's not actually scientifically proven. So maybe you're just jerk that could use a Ph.D. in humility - RHF could teach you. :lolspin:
Since you do know what an LOD is (I assume), I've already talked to Hanna about their LOD, but I don't feel like sharing it with you, so please go ahead and call them. If you re-read what I posted though, you may realize that I already did post the LOD for you which I was told by Hanna about 2 years ago. I, in fact, did not list the accuracy or I would have called it such.
I didn't say anything about an EMC deviation, I was talking about the LOD.
I said nothing insulting to you, and I'm not sure why you think it's ok to act the way you are? Maybe you're one of those geniuses with no social skills, but that's not actually scientifically proven. So maybe you're just jerk that could use a Ph.D. in humility - RHF could teach you. :lolspin: Since you do know what an LOD is (I assume), I've already talked to Hanna about their LOD, but I don't feel like sharing it with you, so please go ahead and call them.
If you re-read what I posted though, you may realize that I already did post the LOD for you which I was told by Hanna about 2 years ago. I, in fact, did not list the accuracy or I would have called it such. I didn't say anything about an EMC deviation, I was talking about the LOD.
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As someone who holds a PhD in Analytical Chemistry, it surprises me that your first response to sub-par Phosphate levels wasn't to dose a liquid potassium phosphate supplement such as Seachem Flourish Phosphorus. The fact that you have detectable nitrates and undetectable PO4 suggests that your system is heavily PO4 limited, which isn't common but will cause polyp abnormality and STN if untreated. I wouldn't go about trying to raise the level by feeding, without having measures to deal with the increase in dissolved organics (Ozone, aggressive carbon use etc)
reefmutt
Active member
Po4 is something that a reef usually accumulates so easily... Taking the gfo off line was a good first step.. Not so sure dosing po4 was necessary so soon..
Even getting a 0 reading on your checker- especially after removing the gfo- does not mean the corals are not getting enough po4...
You know, to me, those coral shots you posted don't look so bad...
Do you have new or more shots and maybe a fts?
Have you considered an amino supplement?
Or adding a couple more fish?
Or reducing your skimmer performance by either shutting it down for a few hours a day or reducing the air (if it's controllable that way..)
I just think adding po4 should be a last resort.... I do applaud your keeping track of your additions, but... I don't know, I just think you could get your po4 without adding actual po4..
Letting it occur or develop naturally will make the corals much happier, imo...
Even getting a 0 reading on your checker- especially after removing the gfo- does not mean the corals are not getting enough po4...
You know, to me, those coral shots you posted don't look so bad...
Do you have new or more shots and maybe a fts?
Have you considered an amino supplement?
Or adding a couple more fish?
Or reducing your skimmer performance by either shutting it down for a few hours a day or reducing the air (if it's controllable that way..)
I just think adding po4 should be a last resort.... I do applaud your keeping track of your additions, but... I don't know, I just think you could get your po4 without adding actual po4..
Letting it occur or develop naturally will make the corals much happier, imo...
Phos remover and skimming both can remove phosphate and trace elements. I had similar problems for years and found that addind trace amounts of Iodine fixed the problem. There are other trace elements that might be needed as well. They are just easy to overdose. Good luck.
Jeff
Jeff
Scubajoe1
New member
Had the T5S for at least 6-8months
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