Phosphates readings? Can it be true?

[bellasdad0911]

I purchased a Hanna meter for my phosphates just so I can be absolutely certain my levels were correct. I had algae growth on my overflows that just wouldn't go away. My API kits always showed zero. I decided that couldn't be correct so I too my water to a local reef shop and they told me it was
.08ppm using a Red Sea kit. That made more sense. So I did a good cleaning and small water change added knew bulk reef supply phosphate media ( the brown granules ) and after 2 days I went back to get a second reading. That time it was zero. Now that being said we discovered the kits were expired. So possibly the 1st reading was wrong. I have started the Red Sea no3 po4 dosing for about two weeks and the algae has slowed down to almost nothing. I did get some sps color fade but after a few days of heavy feeding ( I wash and strain my cubes under fresh water now ) everything looks great. So my question is, can I be for certain that the reading is dead accurate and I can now relax? Let me add I did the test twice in disbelief and also tested my freashwater tank that was off the charts at 2.50 and the bike turned blue.

 

[PSLReefer]

Your algae is what caused a false zero or low reading, since they were "eating" the phosphates.

 

[madweazl]

My experience:

Hanna ULR - .049

Triton
P - 0
PO4 - 0

All I can say is watch the corals and make a decision based on that.

 

[jsker]

@PSLReefer is correct. For true reading, you wanted the @Hanna Instruments HI736, I will let Hanna chime in.

 

[bellasdad0911]

Your algae is what caused a false zero or low reading, since they were "eating" the phosphates.

This is the extent of my algae. None on the rock or substrate and none on the glass. If it is in fact a false reading, how would I know exactly where it is?

 

[PSLReefer]

I would say get the algae out and retest a day later but I'm not an expert... one word of advice, be careful not to spread the strands cleaning it out if it's confined to the overflow, so to not spread the growth to the display.

One word of advice, if you have algae, you have elevated phosphates. It's a good indicator they are building up a bit, usually.

 

[bellasdad0911]

Algae is only on the overflows. None anywhere else. I have a hose that I bologna cut the end and I suck the algae off, plus my urchin and turbos mow it down nicely. Has anyone ever used caribsea phosbuster? I used to use the white bottle version back in 2002-2003 and it worked great.

 

[2Wheelsonly]

Testing po4 sucks, po4 test kits cause more harm than good because people react based on what the kit shows. Simply look at your corals and make a move based on that. In my years of reefing, there is one thing i'm certain on. If you don't have algae on your rocks and glass then your numbers are fine; if you have brown corals and algae on rocks/glass you need to work on better husbandry. Every now and then I test po4 for the hell of it...sometimes it's 0.02 then it's 0.08 then it's 0.01 or 0.03...one thing remains the same. NO algae on glass or rocks. Test kits don't account for what's eating your po4 or tell you how rapidly po4 is being depleted hence why I think they cause more harm than good.

Throwing a bunch of GFO in a reactor based on some stupid test kit reading it a recipe for disaster. I speak from experience; I can't tell you how many corals iv'e killed by over-reacting and using GFO. Keep it simple, if your glass looks good then chillax bruh!

Looking at your display tank is the best test kit on the market.

 

[madweazl]

... Every now and then I test po4 for the hell of it...sometimes it's 0.02 then it's 0.08 then it's 0.01 or 0.03...one thing remains the same. NO algae on glass or rocks. Test kits don't account for what's eating your po4 or tell you how rapidly po4 is being depleted hence why I think they cause more harm than good...

Looking at your display tank is the best test kit on the market.

.02-.08 is with the margin of error for the human factor and the test kit as well as being a small window regardless. If tested often and everything else being equal, you could certainly measure consumption if you knew what you were introducing to the water. As to your actual point, I do agree though with the exception of no algae growing on the glass (please tell me how this is achieved LOL).

 

[2Wheelsonly]

.02-.08 is with the margin of error for the human factor and the test kit as well as being a small window regardless. If tested often and everything else being equal, you could certainly measure consumption if you knew what you were introducing to the water. As to your actual point, I do agree though with the exception of no algae growing on the glass (please tell me how this is achieved LOL).

Go look at a neglected tank and you will see all sorts of hair algae growing on the back.

 

[Hanna Instruments]

My experience:

Hanna ULR - .049

Triton
P - 0
PO4 - 0

All I can say is watch the corals and make a decision based on that.

This is the extent of my algae. None on the rock or substrate and none on the glass. If it is in fact a false reading, how would I know exactly where it is?

Testing po4 sucks, po4 test kits cause more harm than good because people react based on what the kit shows. Simply look at your corals and make a move based on that. In my years of reefing, there is one thing i'm certain on. If you don't have algae on your rocks and glass then your numbers are fine; if you have brown corals and algae on rocks/glass you need to work on better husbandry. Every now and then I test po4 for the hell of it...sometimes it's 0.02 then it's 0.08 then it's 0.01 or 0.03...one thing remains the same. NO algae on glass or rocks. Test kits don't account for what's eating your po4 or tell you how rapidly po4 is being depleted hence why I think they cause more harm than good.

Throwing a bunch of GFO in a reactor based on some stupid test kit reading it a recipe for disaster. I speak from experience; I can't tell you how many corals iv'e killed by over-reacting and using GFO. Keep it simple, if your glass looks good then chillax bruh!

Looking at your display tank is the best test kit on the market.

Phosphates can be impacted by improper storage/transport of water samples prior to testing. Its usually best practice to test nutrients immediately after sample is taken from source. Also time of day can impact results as the zooxanthellae inside the coral tissue use nutrients for photosynthesis, its best practice to try and test the same time of day to prevent inconsistencies from lighting cycles.

Phosphate testing has more to do than just algae. It also affects skeletal growth and calcification rates of many SPS species. You may not have a lot of algae but still have high phosphate which has a negative impact on coral health / growth.

We recommend the HI736 ULR Phosphorus Checker for reef tanks and it has an accuracy statement of ±5 ppb ±5% of reading. Keep your reading on this Checker greater than zero but less than 15ppb. Both the HI713 LR Phosphate Checker and HI736 ULR Phosphorus Checker are measuring orthophosphate concentration.

 

[bellasdad0911]

So after stirring up my sand bed I got this reading. Could this be correct? I did a dose of phosbuster after doing so to hopefully knock that number down. Thoughts??

 

[madweazl]

What do you mean by can it be correct?

Got my latest Triton results back:

Triton - .048
Hanna ULR - .150

Tank looks fine so, whatever.

 

[jsker]

So after stirring up my sand bed I got this reading. Could this be correct? I did a dose of phosbuster after doing so to hopefully knock that number down. Thoughts??

It should not make a difference is the sand bed is stirred or not. Make sure the vials are clean, no air bubbles in them, and make sure all the powder is in the vial. I took me a few times to get it down to where I was getting a correct reading consistently.

 

[jmp21677]

I try for a reading of 0.02-0.04. I don't want 0 because I see negative results in the corals

 

[CodyRVA]

Phosphate testing has more to do than just algae. It also affects skeletal growth and calcification rates of many SPS species. You may not have a lot of algae but still have high phosphate which has a negative impact on coral health / growth.

Exactly. Recently saw my PO4 spike to .75 ppm, no algae what so ever.

 

[bellasdad0911]

Ok, I will have to retest again and see if it changes.

 

[Hanna Instruments]

might be useful for this thread, http://hannainst.com/resources/aqua...ates-in-your-reef-tank--hanna-instruments.pdf


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