Pinpoint PH

[sparky0028]

I have had the monitor for about a month so I figured it was time to calibrate and clean. I spent over 45 minutes trying to adjust and stabilize the readings.
The question here is. Should it take this long or am I going about it the wrong way? As instructed I cleaned the probe with fresh water and a brush. Then poured the calibration fluid into two seperate continers and had a container of fresh water for rinse as well. I started by getting a reading of the 4.0 and 7.0 without any adjustment. The reading was high on both ends by .4-.5 so I adjusted lower and re-dipped. I did this over and over numerous times until I got the reading as close as I thought it could get. 3.99 and bouncing to 4.0 and 7.01 and boouncing to 7.0. The point here is this was over 45+minutes. Should it take this long and why when I move the wire lead does the reading bounce? How much role does 4-5 degrees difference in water temp play? My friend has the same unit and this morning probes are in the same tank water side by side reading almost .2 points difference. Is this normal even though calibration was pretty much the same?

 

[brooklyn johnny]

Sparky, I have used these units for years and stand by them. I recently had a problem with one of my units and contacted American Marine, and was forwarded to a very helpful guy named Lou, at (914)522-0077. My unit was replaced and works like a champ.
It should not take this long, and there are many reasons the probe and/or unit might go bad. I'm not sure if it makes a difference, but it was always suggested to me that saltwater aquarists calibrate with 7 and 10 fluids instead of using 4, because we'll be using the probe in alkaline conditions. I also put the meter right in the pouch the fluid comes in, because an outside container could change the pH of the fluid when poured in there.
Anyway, without going on I suggest you call Lou, as he works with these all day and will be able to tell you what the issue is. Whenever I run into problems with anything, in this industry nine times out of ten you'll find someone helpful on the phone if you contact the manufacturer...
Let me know if he helps...

 

[sparky0028]

Thanks, right after I posted I called American Marine because I was calibrating for about a 1/2 hour and still having problems. Wouldn't you know Lou answered the phone and was very helpfull, he said that I was being a little to critical with the numbers, that a .02 swing while calibrating was acceptable and that the unit and probe was ok. It still took 45min + to finish.
OT -The reason I started calibrating was my PH went up to 8.54 the other evening. With help from you and Kip I decided to add a K-reactor with a Liter Miter for top off. I am still trying to get my numbers stable, should I put a timer on the pump and run it opposite the photo period so the PH has less of a swing. If I do this I would have to top off the same amount in say 12 hours instead of 24, would that help.
Once again thanks for the time.
Sparky

 

[brooklyn johnny]

What is your pH swing, calcium, and alkalinity? How much kalk are you adding to your reactor? What are your other means if any of calc and alk supplementation?
These answers will help...

 

[sparky0028]

I started the raector on 5/11/04 with 3TBS of kalk, and then add 3TBS twice since then. Here are the last 4 weeks.
5/11 5/17 5/26 6/3
PH 8.28 8.34 8.36 8.33
Temp 81.1 79.7 80.8 79.7
Sg 1.025 1.025 1.025 1.025
Alk 3.77 3.70 3.70 3.66
CA 420 410 390 400
MG 1410 1320 1305 1300
I have added Tech A & B once a week to try and get the Alk and CA up, 30ml of each plus and about 60ml of mag the other day. I know I have readings later then 6/3 but I guess I forgot to plug them in at work. I am toppping of about 2.5-2.75L per day to match evaporation. The tank is a year old and 100 gals.
Thanks
Sparky

 

[brooklyn johnny]

Readings look good to me... why would you change anything?

 

[sparky0028]

From reading other members tank stats I thought my alk and ca were a little low for the acro's that I was adding. I was also concerned about rise in PH to 8.55, and I notice a area of zenia's that were total recessed and some of my gsp was totally closed, very unusual for my tank at night.
So you think these numbers are good and to contiune what I am doing.
Sparky

 

[brooklyn johnny]

Many reefers go out of the way to get high readings of alk and calcium, but you'll find that most people will be happy with dkh around 3.5 meq/l and calcium around 400. 8.55 is nothing to worry about in the short term... many experts, including Anthony Calfo, recommend 8.4 to 8.6 for pH. Mine naturally runs low but all is well so I don't fix what isn't broken. I imagine that spike was just after filling your K reactor. pH fluctuation worries me more than the number itself. My opinion is that you are fine...

 

[sparky0028]

Thanks
I guess I will try and hold these numbers, I have seen your tank, it's awesome, and that speaks for itself.
Sparky