3 month tank, PO4?

[Res_Ipsa]

My 60g tank is 3 months old and most of my parameters have been pretty stable the last month or so. However, I just bought a Hanna ULR phosphate checker to start measuring PO4.

As you can tell, my PO4 is reading 0.45 ppm. I’m going to retest to confirm, but assuming that’s correct, what’s the next logical step? Start running some GFO?

I do a 5g water change once a week and the rest of my parameters are within normal ranges. No magnesium test yet though.

 

[Bayareareefer18]

Any livestock?

 

[IslandLifeReef]

The next step is to determine your NO3 levels. You need both to get rid of each naturally. Also, I would focus on your fish food and feeding habits.

 

[Sod Buster]

That ULR requires a math equation. I'll post the chart. Don't panic and do drastic things, take it down slowly under the yellow line. The formula is in the directions if you'd like to check the math.

You are 0.138ppm. A bit high

 

[Res_Ipsa]

@IslandLifeReef - Nitrates climbed from 2.5ppm to 10ppm after I removed my Purigen two weeks ago. I just added it back in so they should be falling.

 

[Sod Buster]

Basically take that # on the device and multiply it X's 3.066 to equate to phosphate, that number divided by a 1000 ='s phosphate in parts per million.

 

[Res_Ipsa]

Tank is stocked with:

2 clowns
Midas blenny
3 springer damsels

10 corals - mostly small frags, one medium hammer

18 blue legged hermit crabs, 10 mixed trochus and Mexican turbo snails, and a sand sifting starfish.

 

[Res_Ipsa]

@Sod Buster - I grabbed the latest checker which I don’t think needs the conversion?

 

[DarkSky]

Basically take that # on the device and multiply it X's 3.066 to equate to phosphate, that number divided by a 1000 ='s phosphate in parts per million.

You're thinking of the under Phosphorus ULR checker. He has the newer ULR that does the calculation for you, as seen on the screen (ppm, says phosphate not phophorus).

This is the older model which requires conversion.

 

[DarkSky]

@Sod Buster - I grabbed the latest checker which I don’t think needs the conversion?

You're correct. Yours does not need the conversion.

 

[DarkSky]

My 60g tank is 3 months old and most of my parameters have been pretty stable the last month or so. However, I just bought a Hanna ULR phosphate checker to start measuring PO4.

As you can tell, my PO4 is reading 0.45 ppm. I’m going to retest to confirm, but assuming that’s correct, what’s the next logical step? Start running some GFO?

I do a 5g water change once a week and the rest of my parameters are within normal ranges. No magnesium test yet though.

If you decide to use GFO, use a small amount. Perhaps start with a 50% water change and a tiny amount of GFO. Dropping phosphates quickly has always led to problems in my tanks.

 

[Sod Buster]

Ha! I see the ppm. Nice. You are ok. Sorry for all the excitement.

 

[Res_Ipsa]

Thanks for all your responses so far. Suspecting a bad test, I just re-ran it for a result of 0.20. Happy with a lower result, but I’ll test a third time to see where the average lies.

 

[Dkeller_nc]

Your tests should be a LOT more consistent than that. There are some tricks to using the Hanna Checkers. The first is that the orientation of the vial in the checker must be consistent between zeroing the meter, then reinserting it and starting the 3 minute countdown timer after the reagent is mixed into the water sample (you are using the 3 minute countdown timer initiated at "C2" by holding down the read button until the timer starts, correct?). The second trick is that the outside of the vial must be scrupulously clean and remain that way between zeroing the meter and reinserting it with the reagent mixed in. That means not holding the vial on its sides as you mix the reagent, as fingerprints will increase the reading you get over and above the true phosphate concentration.

Finally, you must get all of the reagent in the packet into the vial. This isn't easy when you first get the meter; some order micro funnels off of Amazon for the purpose. I use a small square of wax paper, creased in the middle - hold the crease in the center of the vial, and give the back of the paper a gentle tap.

 

[Res_Ipsa]

@Dkeller_nc thanks for the lengthy and informative post. I doubled down on checking the cuvette for fingerprints and used scissors to cut the reagent packet instead of tearing it by hand.

It seems being more precise on the testing steps is yielding results more in line with visual observations than the initial 0.45 ppm reading would suggest.

I made about 25 gallons of saltwater anticipating needing to do a bigger water change. Glad I will probably only need one to get the parameters back in line at <0.1.

 

[saltyfilmfolks]

You think your Po4 is bad?
Check out this guys poor reef.

https://www.reef2reef.com/threads/my-home-tank.296635/#post-3626579

 

[Dkeller_nc]

You honestly don't need a water change. 140 ppb of phosphate is absolutely fine. What you don't want to do is try to keep under a particular arbitrary number (such as 100 ppb).