What does Instant Ocean Salt set ph To?

[jpierson77]

I htink i have a bad pinpoint ph monitor, i just checked my tanks ph and it reads 7.8. I made up some fresh water with instant ocean salt and as a test i stuck my probe in it and it reads 7.9. Anyone know what this salt buffers to? Also anyone with a pinpoint probe, i recalibrated with 4 and 7 test solutions, when i use a 9 test solution it reads 8.8. Any ideas?:confused:

[reefshadow]

I couldn't tell you about the salt, but I have a milwaulkee meter that is funky hard to calibrate at times. A few q's/ideas for you... How old is the probe? They do seem to have a useful life, mine will live for about a year and then kick the dirt, I simply cannot calibrate it accurately anymore. My other though was to wonder how fresh the solutions you are using are? They should really be one shot only and then discarded.

:)

[crustin]

i test io the other day with a milwaukee , it was 8.0 (unless mine is off, lol)

[skeeter_ca]

Mine always test at 8.3. It has never changed but i do use RO/DI water to mix it in. If you use tap water it might fluctuate. Also make sure you ph meter is calibrated.

[Baggerhog]

I use a Milwalkee and change with ro/di water and mine tests at 8.4 every time.

[crustin]

dam, we all get different reading, wonder what the ph in our tanks really are?

[GoldStripe]

depends on how long you wait after making water. pH will stabilize after 24 to 48 hours or so I've read. i've never tested my pH on brand new water but my tank is always around 8.2-8.4

[crustin]

well test it and lets see

[GoldStripe]

lol, good excuse to start the wc process huh?

[crustin]

yea go head, i want to know what your readings are

[GoldStripe]

It is actually time for a wc so i'll probably get the water mixing tomorrow, check pH as soon as the salinity is right, then wait a day or so and check it again

[crustin]

good , please post reply

[GoldStripe]

will do except one minor thing, my salt is not IO right now. I'm trying out that new Red Sea salt but I'll post results regardless

[IslandCrow]

Someone correct me if I'm wrong, but the PH of both your tank and newly mixed SW is highly dependent upon the amount of CO2 present in the water. If you're vigorously aerating the water you mix, then 7.8 certainly does sound pretty low. Of course, that could also just mean you have a lot of CO2 in your house. Try mixing it up outside with a powerhead or something that's going to provide a good deal of agitation. It should definitely test higher then. I'd guess around 8.2-8.4, but that's really just a guess.

[crustin]

i use mag 7 in 30g trash can 24hours before i add salt(instant ocean) my reading was 8.0

[crustin]

reading was 8.0 after adding salt

[fsn77]

<a href=showthread.php?s=&postid=7665023#post7665023 target=_blank>Originally posted</a> by jpierson77
Also anyone with a pinpoint probe, i recalibrated with 4 and 7 test solutions, when i use a 9 test solution it reads 8.8. Any ideas?:confused:

The probe, according to the manual, is good for up to 18 months. If it's older than that, or won't stay calibrated, it's time for a new probe. If it was stored dry for any period of time, it could require replacement. The next time you buy calibration solutions, try to get some 10 (usually it's 10.01). Calibrating with 4 & 7 and then trying to read accurately above 7 can really be a crapshoot. The calibration is good a little beyond your calibration points, but if the monitor doesn't have any clue what pH 10 should be, it's not going to accurately produce readings of 10 (or probably even 9 for that matter). To really test if your probe is any good, see if you can get ahold of some pH 10 solution, calibrate your probe with 7 & 10, then put it in the 9 solution and see what it reads. That 0.2 difference in your reading vs what 9 should read is probably due to the fact that the monitor hasn't been calibrated beyond 7.

Btw, some water I mixed up on Thu with Reef Crystals (no aeration or mixing since then) reads 8.0 on my PinPoint monitor that was recalibrated the same day.

[jpierson77]

Thanks for all the posts i was out all night last night so im just getting around to checking these. I switched to another probe i had that was stored in the pinpoint storage solution, and i got a reading of 8.1 on my new sw with IO. The PH in my tank is now looking more normal at 8.2. Looks like my probe took a digger! Ca reac. effluent, so who knows why the thing crapped out. Addtionally i have little bottles of test solution form aquamedic that i have been using these have to been good for more than one test right?
One point that was brought to my attention is the Ph and alk of the water we use to make our new salt water. The thought was that this could possibly part of the difference in all the new sw readings. I live extremely close to the mountains so we are the first water out of the water out of the river. Everyone in my area uses tap water with some de-chlor, with no problems. My tap ph is 7.6 but i have not tested alk.
Last question what is the reason for letting the new sw sit for 24hrs? I dont let mine sit near that long.