pH Meter Reco – 10/20/07
Good morning Crew!
<Afternoon Gans!>
Hope you are all doing well. I am looking to buy a PH pen/meter.
Would you recommend something like this
http://www.petsolutions.com/default.aspx?ItemId=10600160&EID=10600160&SID=FROOGLE
or what I pay is what I get in this case?
<Milwaukee has been making pH meters for a very long time. This is a good inexpensive pH meter and should last you for a while.>
Thanks
<Your welcome – Brian Griffin>
Gans

Alkalinity Testing Meters?   8/26/07
Hello, Crew.
<Bob>
Like many color blind aquarists, I have trouble reading the subtle color changes (titration method) when doing water tests. Calcium and alkalinity being especially difficult (I use Salifert test kits for both). I have researched and discovered a number of water testing meters from Pinpoint, and even a phosphate meter made by a company called Martini Instruments.
<Like that name>
Any experience or thoughts on these companies products (or others?)?
<I like the Hach, LaMotte (and co.s that re-label their products) simple/r colorimeters, spectrophotometers and kits that go with them>
Also, I have not been able to uncover any equipment/meter capable of giving me an alkalinity reading.
<They are about... see the above's websites...>
Are you aware of any? If not, any recommendations on a traditional test kit for alkalinity that might have a more obvious reading/color change than the Salifert kit?
Thanks for your thoughts!
Bob
<And take a read on WWM re this issue... the indices, search tool... Bob Fenner>

Re: Help! My tank looks like a plantation! Now e- pH measure...  – 08/01/07
Thanks Bob. Previous to the disaster, the parameters seemed perfect. I was using a Pinpoint Ph monitor and the new probe is faulty (says me).
<Mmm, unusual... perhaps just needs to be calibrated... Otherwise I'd return>
I overdosed the tank with buffer which pretty much caused disaster.
<... please see WWM... All such changes need to be made gradually VIA pre-made/mixed water>
I contacted the manufacturer, he told me there's no such thing as a reliable Ph test
<What? Ridiculous>
which makes me wonder why I bother with the Ph monitor if it's not reliable despite the promise that it is.
<These tools are accurate and precise...>
I should probably get some more snails. I haven't seen the Nassarius for a bit.
Thanks so much again,
Lisa
<Keep reading. RMF>

Re: Was: Help! My tank looks like a plantation! pH probe. – 08/01/07
I calibrated it twice when it seemed to be reading low after the first
week. Is it possible the calibration fluid is bad?
I'm using the packets 7 and 4.
<Not likely... I think you have a bad probe... Perhaps a manufacture defect, broken or let dry out too much... Time to send it back. BobF>
Thanks,
Lisa

Setup and Servicing Info, Library   3/3/07
First of all, Hi WWM gang!
<A big hello to you Aaron!>
I looked on the site but didn't find the info I needed.
<This page might help:  http://www.wetwebmedia.com/yourlibfaq2.htm >
I own/operate an aquarium setup and servicing/mobile store business. I do the freshwater and a friend with 14 years of saltwater experience does that side of things. He has taught me much, but I would like to learn more. Do you have any suggestions on books or other comprehensive info sources or guides?
<Oh yes!  The first book I would start with is "The Conscientious Marine Aquarist" by Robert M. Fenner it is the best overall book out there, in my opinion.  Another basic book is "The New Marine Aquarium" by Michael S. Paletta who also authored "Ultimate Marine Aquariums" John H. Tullock also has a nice one on creating microcosms titled "Natural Reef Aquariums".  I hope this gives you a good start.>
I want something that starts from the beginning and goes to the advanced, not necessarily all in one book of course!! What about electronic testers? What types should I get for my line of work?
<I'm guessing the best you can afford, but for specifics I'll to defer this question to Bob... RMF any recommendations?> <<I like the Milwaukee line for "down and dirty" regular aquarium use. RMF>>
Aaron at Tanks-A-Lot
<Mich at WWM.>

Where can I get buffers for calibration?
I've received an electronic pH tester, but it didn't come with calibration buffer...
I need a buffer with pH or 7.01 and then either 4.01 or 10.01 to calibrate it.
Where can I buy this (or what can I use?)
thank you,
Luke
<Mmm, I would buy such "standards"... either from/through the industry (try Marine Depot or Custom Aquatic... links on WWM, or through a chemical supply biz on-line. Use your search engine and the term "pH standard solutions". Bob Fenner>

pH measurement variation, Electronic  2/18/07
Great site guys - I'm a month into a 44 gal (US) tank, just two clownfish, cleanup crew and live rock.
I use an electronic pH monitor, and wanted to share an unusual source of error.
<Okay>
One afternoon the pH (normally around 8.15) was reading 7.94. I nearly started to add lots of Kalk, but I was puzzled how that much water could change that fast. It hadn't - one of my snails had crawled down the electrode, and slimed it through the plastic outer shield. Once he was gone, normal readings were restored...
<Interesting>
Now if the pH electrode had been on a controller wired to the Kalk pump, I dread to think what could have happened. I'm still thinking how to make a snail guard to keep them far from the actual glass bulb.
<A good idea>
Oh, for those folks asking after pH standards, my vote is for Omega pHydrion kit - 3 lots of 10 powder capsules (pH 4, 7, 10), all for £15.
<Thank you for this "plug">
Each make 100 ml, with 3 month shelf life.  If you really want to make your own (or just to check the calibration has worked), the easiest is 0.01M borax at pH 9.18, but check the temperature, and it goes off with CO2 in the air, so make it fresh.
<Ah, yes>
National Bureau of Standards has good info on buffers - sadly I can't see one around pH 7 from kitchen materials.
<Very pure water...>
Thanks
--David
<Bob Fenner>

Which would you choose? Electronic test gear   9/1/06
Hello to everyone at WetWebMedia.com,
   <And to you Aaron>
  I can't stress how helpful this site is in both setting up and maintaining an aquarium, and want to say thanks for everyone's effort.  
<Welcome>   
  I would have to say that I am fairly new to the whole saltwater reef situation, about 9 months in to my little 24 gallon tank and hooked pretty good, gotta have a bigger tank.  I have two Croceas that are growing very well and open nicely.  The one that I have had for about 5 months now has packed on about 3/4 inch of new shell, is that good?
<Oh yes>
  I have run into almost every single common problem known to this hobby.  Right now I am in a losing battle with stupid CYANO (I think it's actually kind of interesting stuff)
<Is>
, but I will win in the end.   
  The situation that I am in right now is kind of interesting, but first a little background.  I decided to try to figure how to be lazy when it came to doing those annoying colorimetric drip tests and super inaccurate hydrometers.  I decided to purchase an American Marine PinPoint Salinity Monitor.  I found out that my hydrometer read 1.024 but the salinity monitor read 1.031 equivalent in mS after calibration.
<Mmm... this is way too "off" a difference...>
  To help the environment and my already hemorrhaging wallet, I decided to get the AC adapter instead of using batteries.  There was a major problem, the reading was fluctuating by .7 mS.
<!>
  I worked with the president of the company for about four months, I became his problem solver.  I found out what the problem was and solved it, the ac adapter had to be regulated to 9 volts.
<Oh! Yes>
Learned a lot about circuits and transformers in the process.  I also get to beta test their new nitrate monitor when they get it, can't wait.
   <Very good>
  This is where my question comes into play.  I already have a pH monitor and a Salinity monitor.  Until I got the pH monitor I didn't realize how big of a pH swing there could be between night and day.
<Some systems much more than others...>
As my reward for solving this problem I am able to get anyone of the American Marine monitors or controllers.  I don't know which one to choose, and was hoping you might be willing to help.  If you had your choice which one would you choose, not including the pH monitor or the salinity monitor?  would you want a pH controller, a ReDox controller, calcium monitor?  You get the idea.  Their website is http://www.americanmarineusa.com/ and their product is top notch.
   <Mmmm... for most cases, folks the calcium would be best... Myself, I'd get/use the Redox... if I had, intended to use Ozone, other means of adjusting such... or was really "into" monitoring water quality for other purposes (e.g. aquaculture)>
  I have another question for you but this is long enough as it is.  A small glimpse:  Mass crustacean death in my tank.   
  This doesn't need to be posted in the question of the day because this isn't particularly useful to anyone else, I wouldn't think.
<You are far from correct here. Your experiences, their relating are of high interest and use to others>   
  I thank you for any help you can shine down on my situation.  I do apologize for how long this message is.  Keep up the awesome work.  Conscientious Marine Aquarist and Reef Invertebrates are both highly informative.   
  Aaron
<Thank you. Bob Fenner>

pH probe calibration
hope you guys are having a merry xmas.  one small question.  I have 2 electronic ph meters reading .25 different.  is there a homemade solution or method to calibrate these?
the 4.0-7.0-12.0 solution packets that they came with, but used them up a while back.  cant seem to find where to get more, but figures there was an easier way? thanks for the help. Neil
<There are "stock solutions" one can make at home from "household" materials... but... I would purchase new standards (you can find them using your computer's search engines with the term: pH standards.) And, if it were me, mine, and the two were still a quarter point different, I would send them into a lab for testing there. Bob Fenner>

Lighting interference with pocket pH tester   1/12/06
Belated Happy New Year!
<Thanks>
I thought I would pass on an experience I have had recently that cost me dearly. I bought a Milwaukee pH tester, waterproof, very nice. Next I bought a new Jebo pc fixture with 2 65W half 10000K and half actinic lamps. This fixture has an external ballast which is very nice, lighter in weight and easier to hang above the tank.
Now for the bad part. When I used my new tester on my tanks, I have 2, it read perfectly, 8.2 to 8.3 on each tank. Before I checked my pH levels again I bought the new light and was using it. On my smaller tank the pH was still 8.2 to 8.3 but my big tank was 6.9!! I panicked and got some buffer and started trying to get the pH up. Nothing was working. I don't know how much I finally ended up adding but I couldn't get the pH above 7.3.
Hindsight being 20/20, I realize how big a mistake I made and won't repeat it. But I didn't find out what was the problem until I tried  to show a friend the way the pH tester worked and had it in a cup of water and turned on. It was reading 7.2 in the cup but when I brought the cup up to the top of the tank to test the water there the reading dropped to 5.4! I moved the cup with the tester in it back and forth a few times and watched the reading go up and down. Finally I turned the Jebo light off and the reading stayed put. And it tested the same as the test kit showed.
I never thought about a light fixture interfering with a tester.
<Mmm... RF... electronics...>
Unfortunately I didn't learn until after I burned up most everything in my tank with high pH, 8.8 was the highest it tested. And of course then I started doing water changes and everything I could think of to bring it back down. It seemed to take forever to stabilize. I lost all of my 'pods, some snails, my serpent star, and cleaner shrimp which had gotten so big. I was heart broken for I don't know how long.
The good news is that after what has seemed like forever my tank is back healthy. Even my 'pods are back and I have baby Nassarius snails too. They look really cute in there. I am still dealing with algae problems like a newly cycled tank but it's getting better.
I am telling all of this to hopefully keep someone else from having a similar disaster.
Agnes
<Mmm, Please do consider writing Jebo re this interference issue... Could be very important to their business... especially when the folks at UL catch up with this part of the trade again. Bob Fenner>

Pinpoint ORP monitor
Hello Mr. Fenner, I hope you are having a great day
<we hope you are well too, my friend>
Just wanted to ask you a couple of questions regarding the ORP monitor I recently purchased. I have a 80 gallon tank with a 20 gallon sump, with about 800 gph circulating through it, plus a skimmer connected to a Sanders 25mg Ozonizer. I have not used the ozonizer for about a week, and the Redox levels keep getting ridiculously high. 
<hmm... very surprising without the use of ozone... are you sure the readings are correct? 10X water flow that you have is not exactly dynamic to support such high Redox>
I have a couple of eels a passer angel and a Coney grouper (both fish small). 
<my goodness... with the predators/messy feeders I now seriously doubt that you can naturally get Redox over 400mv without ozone. Do check accuracy>
Since I bought the monitor, the levels have gone from about 500 to 1080! Which is were it currently is registering. I know something is wrong, as the fish seem as healthy as ever, and if those numbers were true I'd be better off trying to keep fish in liquid bleach.
<exactly... the unit is clearly miscalibrated. Over 400mv is very unlikely>
I 've noticed that the monitor has a calibrating knob, but I have no idea how to obtain an exact reference to properly calibrate the monitor.
I have not found any ORP calibrating solution at the all the e-tailers I shop at, so I was wondering if you can shed some light. 
<it is tough to get fresh solution for calibrating a Redox controller. Try the manufacturer or a scientific supply house. Also, know that most probes are only good for 6-12 months. Rarely up to 2 years old>
I know American Marine say there monitors are already calibrated, but I know this cannot be the case with mine.
I appreciate any help you can provide me with.
Thanks, Harold Chamberlain
<if this unit is new then allow American Marine to address the problem They cannot deny that the unit is faulted with readings like that. Best regards, Anthony>  

Testing, Gear Fever
LOL!  I would have to agree with you on that!
I'm looking forward to seeing the schedule posted on the website!
On another note, after reading some of the posts on water testing I noticed you mentioned that the best route was to use digital meters if you can afford them.  Is there any particular brand/model you see fit for the serious hobbyist?
<Mmm, more has to do with actual maintenance of these tools... their careful calibration, storage. I like the "Milwaukee" line on the low-price end, and the Hach on the mid... there are some "high end" ones...>
Am I living in a dream world or is there a product out
there that will measure all of the following: PH, Salinity, Ammonia, Carbonate hardness, Nitrite, Nitrate?
<... reminds me of the line in the "Terminator" movie: Ahnold, "... Plasma rifle with the Laser scope...". "Hey pal, just what you see". Other than pH, you can currently get a mass spectrophotometer (my choice? a Perkin-Elmer)... Do you have this sort of cash? Perhaps you'd like to adopt a fifty year old pet-fish type of guy?>
  In the end I am not against spending a fair amount of money for the ease of use digital would provide.
<Oh, that's more like it. Hard to justify at this point.>
Nice chatting with you....
Craig C
<Bob F>

Testing, Gear Fever
Sorry, I think if I brought a 50 yr old pet-fish guy home the result would be immediate eviction of myself and said party by the better half.  (they tend to be picky about those sorts of things, don't they?)  LOL!
<Ha!>
Seriously though I was almost hesitant to ask that question for the obvious reasons....
I don't have the kind of cash needed for a mass spectrophotometer I suspect.
However, I suppose I could buy a few different digital meters as I go.  I was mostly wondering what, if any digital meters were worth the cost.  It seems like the digital mode would take away the annoyance of waiting for colors to develop, trying to match said colors, and the expense of test strips in the long run....
<I understand... but hasten to add the small hand-helds do have their requisite shortcomings as well... re-calibration, maintaining standards, fragility... Colorimetric assays are fine for most all hobbyists, settings. Bob Fenner>
Thanks again!
Craig C

pH probe calibration
hope you guys are having a merry Xmas.  one small question.  I have 2 electronic ph meters reading .25 different.  is there a homemade solution or method to calibrate these?
the 4.0-7.0-12.0 solution packets that they came with, but used them up a while back. I can't seem to find where to get more, but figures there was an easier way? thanks for the help. Neil
<There are "stock solutions" one can make at home from "household" materials... but... I would purchase new standards (you can find them using your computer's search engines with the term: pH standards.) And, if it were me, mine, and the two were still a quarter point different, I would send them into a lab for testing there. Bob Fenner>

- Investing in a Digital pH Meter -
Hi WetWebMedia,
<Hi, JasonC here...>
I recently started a small marine aquarium business.  Because I have a number of different systems, I often go through a test kit rather quickly.  I've been thinking about the digital testers which are supposedly highly accurate, the only disadvantage is that their an investment. <Well, any piece of equipment that helps you do your job more effectively would be an investment, but the $60-70 you would spend on a handheld meter would be a rather small one, but quite invaluable in the long run.> I really need something quick, accurate, and reliable.  If you could recommend a couple to me I would greatly appreciate it. <I use the Milwaukee Instruments Smart Meter.> Thanks and keep up the good work!
-Alicia
5th Day Aquatics
<Cheers, J -- >

- Re: Digital pH Meters -
Do you recommend any specific digital pH testers? <I thought that I had put that information in my previous response. I've used the Milwaukee Instruments Smart pH Meter with good success... do believe it is a pH44. Cheers, J -- >

Ph Meter Calibration Questions
Hello, oh wise ones.  Have a question, have not used my American Marine pH monitor in awhile and can't find info from the manufacture. I searched the site and did not find. How do you calibrate?  I have new standard solutions #7 and #10.  Any help, as always is greatly appreciated.  Thanks Brian
<Brian- contact the manufacturer directly at: loudell@bestweb.net>

- Electronic pH Tester -
Hey guys hope all are well, quick question, I am wanting to buy a Milwaukee ph tester for Anthony's Kalk slurry method. <Ok.> Which of the Sharp water proof testers would you guys recommend ph 53 ph 44 etc. <Most are very similar, and should probably depend more on your budget. I use a pH 44.> Have a great day! <You too.>
Rocky
<Cheers, J -- >

- Conductivity & Salinity -
Quick question: I have recently acquired a Milwaukee conductivity monitor. I want to use this to monitor the salinity of my tanks, but I cannot find a table for converting conductivity to salinity at a given temperature. I have looked all over the Internet. Any idea where I can find a table or graph? <Well... my only tool available here was the Net, so I used Google to find this: http://www.radiometer-analytical.com/all_resource_centre.asp?code=112&s=go
I think you might find the information you need there, but you should also contact Milwaukee Instruments.>
Thanks, Steve.
<Cheers, J -- >

Automated testing machines???
Hi Guys,
<Hello Paul>
I manage a commercial Live Lobster Facility in New Zealand.  The factory has a total of 17 tanks that run independently of each other and as such water quality testing takes a considerable amount of time every day.  I am keen to find out if there is available any automatic testing instruments to test ammonia and nitrite as these two tests are the ones I carry out on a daily basis.  I have searched the internet high and low, with no success, and am beginning to think such instruments don't exist - CAN YOU HELP?
<I would contact the folks at Horiba (see them on the Net) re such gear. I have used their instrumentation for assaying copper, DO, ammonia... can be fully automated. Bob Fenner>
Regards
Paul Olsen

Digital Testing Equipment 9/19/05
We all know how important it is to regularly test the various parameters of your tank. Of course, that usually brings up the hassle of attempting to distinguish between very subtle variations of hue when using conventional chemical test kits. Plus, I like the more precise readings that would be achieved by using digital test equipment. Do you have any particular recommendations for equipment? It would be pretty cool if there was one device that would read salinity, pH, alkalinity, calcium, and nitrates, but I don't think that is possible using the technology that is readily available today.
<The technology you want is definitely available, just cost prohibitive.  See www.aquaticecosystems.com for digital instruments, meters, analyzers, etc.  The best compromise for the home hobbyist is probably a colorimeter.  Most colorimeters work with a variety of tests and use specially designed lights and light meters to "see" the color of a test sample.  Hannah or Hach just released such a unit that is targeted toward the public and hobby aquarium market, but it is very expensive, as are the reagents.>
So, what units do you recommend for the tasks, and if possible, could you give some feedback as to what priority you would obtain them, and which units might not be worth the cost because they don't provide enough bang for the buck (or they are troublesome to use and keep calibrated)? Feel free to contact me with any questions, comments, or concerns. Mark A. Kaczynski
<Because many of these devices are beyond the interest and budgets of most hobbyists, I don't have a lot of specific information, but I can give some general advice.  pH meters are widely available, simple to calibrate and relatively inexpensive.  The high importance of pH and the low cost/high quality of meters and "pens" makes this a no brainer in terms of "bang for your buck".  Similarly, electronic temperature monitors with programmable high and low limit alarms are a good buy.  Pinpoint recently released a calcium meter which was reviewed exhaustively by Randy Holmes-Farley.  It sounds like it is a good device, but is probably most useful to maintenance providers or those with many tanks, however since calcium tests are notoriously time consuming and hard to read it may be worth considering.  If you are keeping corals, there are a few decent PAR meters available at reasonable prices.  These can be a very useful tool when deciding where to place corals.  My last bit of advice is that while all of these gadgets are certainly nice to have and useful... don't be ruled by them!  Many aquarium gadgeteers become obsessed with maintaining perfect numbers on the readouts of their monitors and forget the importance of simply observing the animals!  Best Regards.  AdamC.>

Monitor probe
Hello Mr. Fenner, I have a quick question about a Milwaukee ORP monitor and controller. I'm not sure If you are familiar with this type of brand. The instructions are not very helpful. My questions is the probe?? Does it sit all the way in the tank or does the first couple of inches go in the tank?
<The first few inches.... they're made to be overall waterproof, but it's best just to dunk the end in a few inches>
Also, sorry maybe two questions/ The instructions say something about a rinsing solution what is this solution and why didn't they include this? 
<Hmm, don't know... add on sale? Good clean water (reverse osmosis, de-ionized, distilled... will be fine here)... here's their URL: http://www.miltestersusa.com/
Write and ask the manufacturer as well! Be chatting, Bob Fenner>
Hope to hear from you soon, Ryan Hebert

EC/TDS Meters
Mr. Fenner,
I purchased a Milwaukee Model SM301 Conductivity and TDS meter, but found that it has very limited instruction on how to read and define the meter reading. I was wondering if you might have any knowledge of this. The following are some of what I am looking for plus any other info you can offer.
<Hmm, would contact the Maker: http://www.miltestersusa.com/ re better, more instructions... and/or the folks who sold you this gear.>
Meaning of mS/cm?
<micro-Siemens per centimeter... a "new" standard of conductivity measure equivalent to "micro-ohms per centimeter"... the company "Siemens" IS that big, influential"... A higher reading indicates more ionic content, higher conductivity...>
The range of the unit is 0 to 1990 mS/cm. What is considered a normal reading?
<Normal for what? Marine, brackish, freshwater, Koi ponds, water for epiphyllums...? Again, I would, will cc Milwaukee Instruments here... Bob Fenner, WetWebMedia>
Leldon

-pH meter woes-
HI crew
I decided to do a water change on my reef tank the night before my wedding and honeymoon. <Congrats! On the wedding that is, not the water change ;) > I cleaned all my powerheads, pumps, overflow etc. just to be on the safe side while I'm gone for the week. I get to my 10% water change which is rodi water with tropic marine that I had heated and circulating for 24 hours. I take my Pinpoint ph meter's probe out of my tank to measure the new water and it had a ph of about 8 so I mixed some SeaChem reef buffer in a cup of RODI and stir it into the salt mix to get too the 8.15 ph level that my tank is at. Then I put the probe back in the tank and change the water. All of a sudden my tank is at ph 8.95 so I freak and switch back half of the old water and the ph goes to 9.05 I add a gallon of RODI and the ph says 8.87 so I think that's odd and I take the probe and test the old water which was 8.15 and it say 9.1 . crap my meter is messed up. I tried to calibrated it with the 7 and 10 solutions and it was all over the place if I tapped the meter it would jump up past 7 to 8 then 5 . so I turned it off for five min and then was able to calibrate it. Needless to say my tanks ph is 7.95 and all my freaking was for nothing. My question is what happened and what should I do now? the meter is only 4 months old. <The first step would be to change the probe and see if it calibrates easily. Otherwise the problem would be with the meter (uncommon) and you'd have to take that up with American Marine. My pH meter finally crapped out a couple of months ago and I haven't really missed it much, it's very easy to get caught up in the numbers when they don't really matter all that much in a healthy tank. -Kevin>

ORP accuracy/calibration 8/15/04
Hello,
<Cheers>
I recently purchased a pinpoint ORP monitor for my 110g reef tank.  I placed the probe in my sump about 4-5" away from my pH monitor as per the instructions.  The instructions also stated it my take 24-36 for a true reading so I waited a couple days.  
<this is true... very good>
I was a bit shocked yesterday when I noticed the monitor said 586mV and this morning it is a little bit above 600mV.  I'm very confused as to how my levels are so high, I do not use Ozone.
<even with ozone, this would be a surprisingly high measurement... the unit is clearly misreading here. 350-425mv is a safe range. Do recalibrate the unit and perhaps give is a few more days to break in. Contact the mfg or your LFS for support if you didn't mail order it (one of the many benefits to supporting your LFS)>
Thanks for your time. Chris
<best regards, Anthony>

- New PinPoint Calcium Monitor -
Hello guys, have any of you used the new Calcium Monitor from Pinpoint (retails for $249)? 
<This item is very new and unfortunately they don't send me new products for testing so no... I haven't used it.> 
Any ideas on how long the probe will remain accurate (just the replacement probe is $199)? 
<No idea at all, but like any monitor probe, I would suggest that you clean it often. Many probes go south prematurely because folks leave them in one spot for as long as they last. But man, that is an expensive probe. Think of the number of calcium tests you could buy for that... knowing the calcium level from minute to minute seems excessive, perhaps even obsessive/compulsive to me, although I'm sure there are some out these who've already snatched these up. I'm going to stick with my titrations.>
Thanks,  Franz
<Cheers, J -- >

Unstable ISFET Probe When Immersed
Dear Crew,
I recently purchased a pen-type pH meter with an ISFET probe. It has a single-point calibration at pH 7.0 that I think is adequate for my aquarium use. I noticed that its readings are accurate and stable provided that I place a drop or two of the test solution on the electrode tip of the probe. When I immerse the ISFET probe into the same solution, the readings are unstable and vary widely. Which pen-type ISFET pH probes will give stable readings when immersed? 
<Paul, I would direct that question to the manufacturer of your probe.>
Thanks very much.
<You're welcome> 

pH testing probes
greeting fishy people,
in my never ending quest for cool cheap gadgets , I came across this soil PH tester . Any idea if this sort of thing would work (assuming it covers the correct range)?
<It may, not familiar with this device>
I currently am using cheapo test strips which provide little to no accuracy given that the color scale jumps from 7.8 to 8.4 ... and of course the color I am trying to match to is somewhere in-between :P  I've read in some of the FAQs that digital PH probes can be found in the $30-$50 range, but have been having a hard time finding such devices.
<try Aquatic Ecosystems, they have a renowned catalog and website>
Being a long-haired, bearded Libertarian, I am a little freaked out about ordering something like this online from a hydroponics store..... we're all being watched.  Any suggestions/ideas/recommendations for these things?
<definitely look into a good digital pH probe, they work well and last when taken care of>
Oh yeah, my system:
180g FOWLR
~130lbs LR
constantly re-arranged sand that used to be about 3 inches deep across the bottom of the tank
Fimbriated Moray Eel (about 90cm) - the one who likes to keep all the sand in one big pile
2 Yellow tail damsels
1 blue devil damsel
1 cleaner shrimp
DIY skimmer, wet-dry filter, rio3100 return pump,  2 Hagen 802s
Ammonia 0
Nitrite 0
Nitrate ~40ppm - a constant battle with the eel
Calcium 490 (source water responsible for 80-100)
Alk 9.3 dKH
Temp 81-82F , quite stable in that range
Phosphates are quite high >2ppm, but I am surprisingly encountering little algae problems.  These are why I am looking into finding a more accurate measure of PH (that and I guess it would just be a good practice :D) so I can try and precipitate them out with Kalk after I get  my calcium down.  Ok, enough rambling.... thanks for your help
Mark
<best, Chris>