PH meter question

Hey all, I've always used the cheapo ph strips w/o a problem but due to my cousins relentless nagging to join the 21st century I finally ordered a digital meter. My question is do I need both the 4.01 & 7.01 cal. solution to get an accurate reading? Also, does it really matter if its the 4.01 & 7.01 solution or can I use the 4.0 & 7.0? Here is the one I ordered...HANNA HI99104 Pocket pH Tester/Meter/Checker, HI 99104 - eBay (item 300195314477 end time Feb-09-08 23:00:00 PST)
Probably gonna end up tossing this one and upgrading to an Oakton or Truncheon because I realized too late that this thing has to be calibrated manually and there are probably other features that I wont like as well. Should have listened and spent the extra $$ on a nice meter in the first place. Oh well, live and learn. Any help would be great. Thanks

[knottyd]

I dont think the solution matters, its just a constant. You cant adjust ph if you don't have something that you know for sure what it is. I don't see why you would need a different tester, it looks functional and Hanna is a good brand. My tester is a manual adjustment ( I think) all is it is a screw or two that you turn to adjust, shouldn't be hard at all.

Thanks for the response knotty but I'm still not clear if I have to calibrate the meter to 4 as well as 7. Also I need a meter with automatic temp compensation and auto cal. - I hate playing around, I'm sort of an instant gratification type person.LOL Also, the more expensive models alert you when the reading is ready. Fortunately $ is not an issue and if(I probably will) get a better one I wouldn't mind donating this one to a person here that needs one. I've been doing some research and I've read that people have had problems with these types of low end meters. ie having to constantly calibrate and also they don't seem to hold the calibration well. My arthritis will make it very difficult to be turning those little knobs. Does anyone have experience with both types of meters?

[green_nobody]

Originally Posted by Dr.Deoverde

Hey all, I've always used the cheapo ph strips w/o a problem but due to my cousins relentless nagging to join the 21st century I finally ordered a digital meter. My question is do I need both the 4.01 & 7.01 cal. solution to get an accurate reading? Also, does it really matter if its the 4.01 & 7.01 solution or can I use the 4.0 & 7.0? Here is the one I ordered...HANNA HI99104 Pocket pH Tester/Meter/Checker, HI 99104 - eBay (item 300195314477 end time Feb-09-08 23:00:00 PST)
Probably gonna end up tossing this one and upgrading to an Oakton or Truncheon because I realized too late that this thing has to be calibrated manually and there are probably other features that I wont like as well. Should have listened and spent the extra $$ on a nice meter in the first place. Oh well, live and learn. Any help would be great. Thanks

Okay, first of all this is a Hanna meter i never seen before and couldn't find on their homepage as well - so could be likely be a fake!!!

second, with a two point calibrated meter - if you put that kind of money on the table - you should use at least 7.01 and 4.01 to calibrated with, even think about buying another 10.01 check buffer if you want to make sure that is fully working.
Those buffer/calibration solutions you get for little money already - i paid 9 bucks per 250ml bottle last time, so it isn't that much if you buy a true hanna meter. also, if you go with a Hanna, buy the Hanna calibration solutions and not something else - this isn't a good point to cut corners nor a smart as the stuff from hanna is often cheaper then all the rest (for milwaukee stuff i paid twice as much).

and finally, if you really used the paper strips the proper way you will save so much money with that meter in one grow already that you will be chuckling later on

besides, this is the best simple 2point model from hanna i ever tried HANNA instruments® :: Testers - not as much comfort as myHI 98130 but more then good enough to get the job done on soil grows. could be even good enough to do DWC if you manage to buy yourself another EC/PPT meter.

Here it is g_n HANNA instruments® :: Testers Thanks for the info, I ordered milwaukee solution(4.01-7.01) so I'm all screwed up here. I asked these people about using a different brand solution with the Hanna and they told me solutions are like gas for your car.. it doesnt matter which you use. These people are idiots. I asked them this because Hanna says only use Hanna products with their meters. You are right, Hanna is right and I am not happy right now. I'm not buying from ebay stores anymore unless they post their phone # This email response stuff is for the birds. Thank you much bro.

[green_nobody]

Originally Posted by Dr.Deoverde

Here it is g_n HANNA instruments® :: Testers Thanks for the info, I ordered milwaukee solution(4.01-7.01) so I'm all screwed up here. I asked these people about using a different brand solution with the Hanna and they told me solutions are like gas for your car.. it doesnt matter which you use. These people are idiots. I asked them this because Hanna says only use Hanna products with their meters. You are right, Hanna is right and I am not happy right now. I'm not buying from ebay stores anymore unless they post their phone # This email response stuff is for the birds. Thank you much bro.

emails are surely for the birds but i'm glade to see tat hanna produces one like yours too, i only know those in total black and not white.
sure, pH buffers are comparable but they meters are designed around the testing protocol of the manufacture as the "razor-blade method" so that you buy there stuff.
okay, i don't know how much they asked for the milwaukee stuff but still i would rather use hanna products here. you can still use it but it could set you meter off by a little if not too lucky (+/-0.02 ~ 0.05 i would say) it isn't too bad but also not as perfect as you would like it to be...

[tokecrazy]

Hey Dr,Toss that tester in the can,I got one and a go-checker by hanna and both are trash.I got a oakton and no problems.The best one I have had so far and this makes 3.The oakton is 100% water proof and easy to use and calibrate.There's no turning screws to adjust it,push a button.You will need both 4.01 and 7.01 calibrate solutions to calibrate it.I find that my oakton has stayed calibrated for about 3 months.I chech it once a month.Best all round for me. PEACE

[green_nobody]

Originally Posted by tokecrazy

Hey Dr,Toss that tester in the can,I got one and a go-checker by hanna and both are trash.I got a oakton and no problems.The best one I have had so far and this makes 3.The oakton is 100% water proof and easy to use and calibrate.There's no turning screws to adjust it,push a button.You will need both 4.01 and 7.01 calibrate solutions to calibrate it.I find that my oakton has stayed calibrated for about 3 months.I chech it once a month.Best all round for me. PEACE

same function you have one the mid to high end meters from hanna too. and i had never a problem with them besides the one i dropped in the lab - that one broke, but you are also no supposed to this with such an tool.

Thanks everyone, I didn't really know what I was looking for in a meter until I actually had one in front of me so I'm going with this oakton Oakton product details I'm sure this will help me sleep better at night. Nothing personal against Hanna but once I have a bad experience with something I just go another route. Thanks again, all the advice was invaluable.

[tokecrazy]

Hey DR.D,I brough two of hanna cheaper models,the gochecker,and the one you have and they craped out.You will need to clean your meter from time to time and calibrate it too.I have the tri-pack storage and maintenace solutions so to keep my meters clean and calibrated.Take a look at Plantlightinghydroponics.com they have what you need to store and clean your meter at the cheaper cost.The Genesis products and they work just fine.I have the cleaner part A and B and there calibrating solution 4.01 and 7.01.The tri-pack has storage solution and PH calibrating solution,4.01 and 7.01.I would get the tri-pack Ph and Storage,than in about month get the cleaning solutions.The oakton pens stay calibrated for a long time and they are easy to calibrate too,no screw driver to set it,just push a button to calirate it.Everbody I have talked to about Ph meters, all say the oakton is there choice of meters.Dont take it wrong, there are other meters out there that are as good or better,but for the price I like the Oakton.Need more just holler. PEACE

[Framster]

I'd definitely get the storage solution to preserve the membrane on the probe. Money well spent.

[Rikki]

Originally Posted by Dr.Deoverde

Here it is g_n HANNA instruments® :: Testers Thanks for the info, I ordered milwaukee solution(4.01-7.01) so I'm all screwed up here. I asked these people about using a different brand solution with the Hanna and they told me solutions are like gas for your car.. it doesnt matter which you use. These people are idiots.

I worked for Hanna for several years and what the they told you is right... You can use any solutions to calibrate pH.
And yes, you need both solutions. The 7.01 will bring the calibration curve offset back to the correct point, then you need the 4.01 so the meter can adjust it's slope. It's a linear curve and you need at least 2 points to set it.

They are some meters from Hanna with auto-cal and ATC (temp) both I think you should stick to Oakton.

BTW, The Milwaukee solutions would have worked perfectly on your Hanna because Hanna manufactures a lot of meters and solutions for Milwaukee. Nobody knows because they are trying to create a fake competition but it all goes back to the same pocket at the end.

[Rikki]

Originally Posted by Framster

I'd definitely get the storage solution to preserve the membrane on the probe. Money well spent.

Well it depends. If you're using your meter frequently, you don't need to. Just pour some 4.01 buffer in the cap and that'll do the job. Not Buffer 7, Not DI Water... Buffer 4.01 is what comes closer to an equilibrium with the electrolyte inside the pH meter.

If you are going to leave your meter on a shelf for several weeks, than you might want to consider getting the storage solutions.

Sales people (which I was) will tell you that you really need this solution. I let you guess why...