PH between 8.5-8.7

[SeeFu]

I doubt the milwaukee fluids are bad if only a couple month old and haven't been opened. If you are saving them after use then well.. they could be who knows what..

I messed my calibration up once doing a manual calibration through apex fusion and not letting the two readings settle properly before hitting next. I have also heard it is better to do the manual calibration vs the automatic mode. I also double check after going through calibration by retesting the probe's readings in both the 7 and 10 fluid. I set the apex to do a 1 minute refresh on readings and I leave the probe in until it gives me an updated reading.. AND I don't know if it helps but I dip the probe in a cup of rodi water to rinse before switching from between tank/ph7/ph10, followed with shaking off any drips.

i do exactly what you do. rinse probe w/ rodi, place in 7 ph solution, wait till apex says next step but i wait an additional minute. then rinse probe in rodi again, place in 10 ph solution and wait a bit before finishing. after calibration i place the probe back into ph 7 solution to make sure it gives me something around 7 ph and then back into 10 ph solution to get a 10 reading. i just recalibrated w/ the auto calibration function again w/ the Milwaukee solution and again i'm getting same PH readings in my tank. its sitting at 8.45 before my lights even come on.

 

[jerrod]

At what level does PH become harmful.

 

[Randy Holmes-Farley Verified Community Expert]

Where was the sample in that curve when you removed it from the tank?

this is my ph graph from apex

 

[Randy Holmes-Farley Verified Community Expert]

At what level does PH become harmful.

Harmful is a difficult question because it depends on what you mean by harmful. In an aerated reef aquarium, the pH will never get high enough to significantly bother organisms unless you dose high pH additives. It is possible that some types of algae that get CO2 directly as CO2 from the water will grow slowly because CO2 is reduced as pH rises. But many types of algae get CO2 from HCO3- and that is generally available even at higher pH.

As the pH rises from about 7.7, past 8.2, and then higher and higher, the likelihood of precipitation of calcium carbonate (especially on heaters and pumps). Once you get into the upper 8's and higher, precipitation can begin throughout the water column, and in a big pH upward spike (say, from limewater/kalkwasser overdose), the whole tank can look like milk (happened to me several times). The precipitation often serves to drive the pH back down by removing carbonate (essentially the reverse of dosing sodium carbonate). Even then, organisms often seem unharmed unless it is a catastrophic overdose and the pH stays high a long time.

At the low end, calcifying organisms have a harder time forming skeletons and shells as the pH drops below 8, and below some point in the 7.7 range, skeletons can actually slowly dissolve. That dissolution goes faster and faster as the pH drops (like in a CaCO3/CO2 reactor.

I discuss these issues here:

pH And The Reef Aquarium
http://www.reefedition.com/ph-and-the-reef-aquarium/

 

[Randy Holmes-Farley Verified Community Expert]

i do exactly what you do. rinse probe w/ rodi, place in 7 ph solution, wait till apex says next step but i wait an additional minute. then rinse probe in rodi again, place in 10 ph solution and wait a bit before finishing. after calibration i place the probe back into ph 7 solution to make sure it gives me something around 7 ph and then back into 10 ph solution to get a 10 reading. i just recalibrated w/ the auto calibration function again w/ the Milwaukee solution and again i'm getting same PH readings in my tank. its sitting at 8.45 before my lights even come on.

Does the APEX read those calibration solutions correctly after calibration?

pH issues with controllers like the APEX seem more common than with stand alone pH meters. Might be related to temperature corrections the apex tries to make, or something else. Make sure the fluids are close to tank temp to minimize that concern.

 

[SeeFu]

Does the APEX read those calibration solutions correctly after calibration?

pH issues with controllers like the APEX seem more common than with stand alone pH meters. Might be related to temperature corrections the apex tries to make, or something else. Make sure the fluids are close to tank temp to minimize that concern.

yes it reads it correctly or at lease close enough. usually within 0.02

 

[SeeFu]

Where was the sample in that curve when you removed it from the tank?

the sampe from the cup is after the dip and then the recovery

 

[Shirak]

Do you put your pH packets in the sump for a few minutes to reach tank temperature?

Next step for me would be to test the tank directly. And maybe try a different location in the sump for the probe? Maybe it's getting wonky from an wire close by which isn't there when you calibrate?

 

[Randy Holmes-Farley Verified Community Expert]

the sampe from the cup is after the dip and then the recovery

OK, so one hurdle down. It read the same in a cup as it did in the tank, right?

 

[SeeFu]

OK, so one hurdle down. It read the same in a cup as it did in the tank, right?

yes same in cup as in tank.

 

[Randy Holmes-Farley Verified Community Expert]

yes same in cup as in tank.

Try aerating it.

 

[SeeFu]

Try aerating it.

no change in ph. i tried it in a small container w/ a cheap powerhead near the surface for 25 min, no change. so then i moved 1/2 the powerhead out of the water so that the propeller was chopping at the water. ran it like this for another 1/2 hr and still no change to ph.

 

[Randy Holmes-Farley Verified Community Expert]

no change in ph. i tried it in a small container w/ a cheap powerhead near the surface for 25 min, no change. so then i moved 1/2 the powerhead out of the water so that the propeller was chopping at the water. ran it like this for another 1/2 hr and still no change to ph.

OK, so next time the pH is 8.7, try aerating that.

What is the tank alkalinity? At 7 dKH, the pH should have dropped to at least 8.2, further if your home has elevated CO2. At 11 dKH, pH 8.4 is about right for seawater aerated with normal outside air.

 

[SeeFu]

this morning i measured alk at 8.43 dkh and ph at 8.46. Today it seems to be lower overall, but we'll see what happens at the end of the light cycle.

 

[Randy Holmes-Farley Verified Community Expert]

this morning i measured alk at 8.43 dkh and ph at 8.46. Today it seems to be lower overall, but we'll see what happens at the end of the light cycle.

Sounds fine.

 

[madweazl]

You mentioned bi-annual calibration; how old is the probe? Mine typically drift high when they need replaced.

 

[SeeFu]

You mentioned bi-annual calibration; how old is the probe? Mine typically drift high when they need replaced.

The prob is a little under a yr old.

 

[SeeFu]

Sounds fine.

so yesterday at the beginning of my light cycle i was at 8.36 ph. by the end of light cycle i was at 8.65. my lights start up at 1pm and turn off i believe at 11pm. There is a 1 hr ramp up and ramp down time along with 1 hr of moonlight period

 

[Randy Holmes-Farley Verified Community Expert]

Try aerating that 8.65 water.

 

[SeeFu]

randy when u're saying to aerate it. will placing a cheap powerhead w/ 1/2 the propeller out of the water in the sump be sufficient? how will i know if the powerhead is actually decreasing PH vs. just the natural decrease in PH? and finally how long do i do this, overnight?