High phosphate

[elviraveloz]

back in 10/12 I upgrated from 55g to 180g never went thru another cycle. In 02/13 I built an algae scrubber double sided. Starting back on 08/13 I stated noticing hair algae growth on the rocks due to high phosphates. Waited until 10/13 to buy GFO. The readings were 0.28, then following day 0.14, 0.17 then back to 0.28 due to that I sent e-mail to Hanna company. Hanna company sent me new reagents with new lot( H130). Yesterday I ran a test it was 0.04, today the reading is 0.17. Is this normal?

Last readings:
Salinity= 35ppt
Nitrate=3
Ca=40ppm
Mg=1300
Alk=8.7
Potassium=440

 

[bertoni]

That sounds like measurement problems to me. Did you dump a bunch of food in the system today? If not, I'd get a second opinion on your meter.

 

[elviraveloz]

No feeding today. Last feeding was last night. Ca reading 440 ppm typing error on comment #1

 

[nystang]

Do you think that measuring phosphate in distilled or RODI water and then readjusting the difference would be the only way to go? I have the same problem with Hanna checker reagent. It reads 0.08 in distilled water, 0.14 in aquarium water so I assume my aquarium water is 0.06.

 

[dkeller_nc]

This might not be germane, but I'll throw it out there just in case. The hanna checkers are just little photometers. As such, they are very sensitive to the background and how that is zeroed out in a sample.

Specifically, it is critically important that you use the same vial for both the zero and the test, that is scrupulously clean of all finger prints, and that the vial is in the same orientation when the meter is zeroed and when it is put back into the meter to read the reacted sample.

Moreover, the reagents involved in the phosphate test aren't terribly soluble. When they tell you to shake the vial for 2 minutes before starting the countdown clock in the meter, they aren't kidding - you must time this shaking period, not guesstimate it.

 

[elviraveloz]

Ok, so that may be the problem, I use two bottles for the reading because after shaking for two minutes the meter turns off when I am using only one bottle. So how you do it?
I always clean bottles for fingerprints.

 

[outssider]

press and hold down the button after the 2 minute shake. This will activate the 3 minute count down.

 

[elviraveloz]

Thank you.

 

[dkeller_nc]

Another tip:

Shake the reagent packet down to get all of the powder at the bottom, cut it open, and pour it out onto a 3" square of wax paper that you've creased about halfway across. Do this before you even put your water sample in the tube to zero the meter.

Then, put your sample in the tube, wipe it for fingerprints, turn on the meter, wait for the "C1" indication, align the "10 ml" to the front of the meter (that's just for repeatability), drop it in, close the cap and press the button. Once the meter displays "C2", start an egg timer for 2 minutes. Remove the vial, open the screw-cap, use the crease in the wax paper as a directional funnel to get all of the powder into the tube, close the tube, and shake vigorously for the remaining part of the 2 minutes on the egg timer.

Once the egg timer goes off, wipe the vial for fingerprints again, re-insert it into the meter in the same orientation that you used for zeroing, and press and hold the button - a 3 minute countdown will start, after which the reading will be displayed for about 1 minute before the meter goes off to preserve batteries.

It's a PITA exacting coordination of manipulation and timing, but once you do it a few times, it becomes second nature.

 

[elviraveloz]

I tried today again. After I shake vial for 2 minutes the meter turned off I hold down the bottom but it went back to C1 indication. Now I'm going to try what dkeller suggest. Why the company didn't calibrate this for three minutes to make this calibration easier.

 

[AFK1911]

I had an issue getting used to my meter as well. Below is how I do my tests. I was getting readings all over the board until I started doing this. I now have confidence in my checker.

- Clean test via with water and bottle brush
- Put about 2 ML tank water in vial, cap, and shake
- Empty vial and fill with 10 ML tank water and cap it
- Open reagant with scissors, do not tear open.
- Push edges of packet together and tap until all powder is in center of packet to be easily dispensed
-Wipe down vial with clean, dry paper towel to ensure no water, spots, or finger prints.
-Press button on meter, once it reads C1, insert vial with "10 ml" printing facing towards you
-Press button again, wait for it to say C2
-Remove vial and empty powder in to it
-Set timer on stove fo 2 minutes and swirl, not shake, the vial for the full 2 minutes
-Wipe down vial again with same clean, dry paper towel
-Insert vial with "10ml" facing towards you and press and hold button until timer starts.

It sounds like a lot, but once you do it a couple of times, it's a piece of cake

After employing this technique, I have been abl to ge very consistent readings

 

[outssider]

+1

this is the way to go. I get very repeatable results doing it this way, remember don't shake vigorously (read the directions). mine actually doesn't time out for 2 1/2 minutes so I can shake for a full 2 minutes then press and hold to get 3 more minutes so the bubbles can settle.

 

[elviraveloz]

After you guys help me, I finally made the mixing on time. Reading was .05. I'm going to try tomorrow again to see if reading is close to .05.
Thanks everyone for your help.

 

[elviraveloz]

Ok. I THINK I MASTER THIS PUPPY! Reading today is 0.03. My next question is I don't want to go below this reading, should I turn off the phosphate reactor?

 

[AFK1911]

Glad it worked for you. I would think the only way to know if you should turn off the reactor is to keeo testing. If it goes below your desired number then turn it off. Keep testing to detect the rise. Turn it back on and test again. This way you should be able to figure out how your tank reacts and come up with some sort of routine for it. Once you do though, I wouldn't just assume all will be good. The only way to tell what's going on is through testing.

 

[elviraveloz]

I'll do that. Thanks

 

[bertoni]

If you turn off the reactor, I'd recommend draining and letting the GFO dry out, to prevent decay. The phosphate level is low enough to be in the error limit of the meter, so I'd watch the animals closely for signs of what to do.

 

[elviraveloz]

Hi Bertoni, What you mean by watch the animals for signs? You mean corals?

 

[dkeller_nc]

If you turn off the reactor, I'd recommend draining and letting the GFO dry out, to prevent decay. The phosphate level is low enough to be in the error limit of the meter, so I'd watch the animals closely for signs of what to do.

+1 to this. If you don't empty the reactor, it will go anoxic, and the bacteria in it will produce hydrogen sulfide gas.

 

[bertoni]

Yes, it'd be the corals that'd show problems.