High pH (8.7)

[Etoimos]

My tank has been setup since May 1st and I've had CUC and some LPS in it since June 25th. I still do not have any fish in it (waiting until after I get back from a rather longish vacation at the end of this month).

My pH has always been high, always in the 8.6-8.7 range. I know higher pH is an indication that the balance of CO2 is off in my tank and that I can does white vinegar to bring it down, but that only lowers it for a short period unless I does it constantly (which I don't want to do). Dosing CO2 is another option, but again, I don't want to do that.

I also need to does 2 Part to get my KH and Ca up (already dosing to bring up the Ca, but the KH I've setup the Apex to not dose it if pH is over 8.6 which it is all the time).

Are there any options for me to lower my pH on a consistent basis? Would having fish in the tank help lower it since they would be converting some of the oxygen into CO2?

Just kind of talking out loud here before going into work to see what might filter in.

 

[homer1475]

High PH is untypical in a reef tank thats inside a home. I would first ask what your using to measure your PH?

 

[Etoimos]

I'm using both a RedSea's test kit and the Apex pH probe (calibrated). Both were reading the same the last time a double checked the pH. The last week or so I have just been going off of the pH probe. I'll do another double check after work today (time to check my other parameters as well).

From everything I've read, the typical problem is low pH so I'm a bit puzzled at my levels.

 

[scuzy]

Sounds like a great candidate for a calcium reactor and ditch the dosing 2 part. I can't get my pH past 8 with a carx

 

[Etoimos]

Sounds like a great candidate for a calcium reactor and ditch the dosing 2 part. I can't get my pH past 8 with a carx

Being new to the SW world, I've not looked into the pros/cons of a calcium reactor. I'm assuming that it would bring up/maintain my calcium levels, but does it help with alkalinity at all? If not, I still need to raise that and as far as I know, doing that is always going to raise the pH.

 

[scuzy]

It's manages both alk and calcium

 

[tmz]

Vinegar will also add organic carbon. Seltzer is a better choice since it just adds CO2.
NSW pH is round 8.1 to 8.2 on average. Recommended range for reef tanks is 8.0 to 8.5. Personally, I like 8.2 to 8.4.

What are the alk ,sg and calcium levels?

Increased aeration via a skimmer and/or surface agitation will enhance gas exchange with the surrounding air leading to a faster rate of equilibartion with the CO2 level in the surrounding air. I'd check that first .

A calcium reactor will lower pH and many have difficulty keeping pH above 8 when using them; typical effluent pH is around 6.5 to 6.9. There may also be impurities in some media products and constancy of dose can be a problem. I haven't taken mine off the shelf in about 8 or 9 years.

 

[Etoimos]

Thanks. Just did a little reading up on it. Sounds like a decent solution, but unfortunately I don't have room to set on up in my stand (60g cube, so only about 2'x2') or a "fish room" to remote it too.

 

[Etoimos]

Vinegar will also add organic carbon. Seltzer is a better choice since it just adds CO2.
NSW pH is round 8.1 to 8.2 on average. Recommended range for reef tanks is 8.0 to 8.5. Personally, I like 8.2 to 8.4.

What are the alk ,sg and calcium levels?

Increased aeration via a skimmer and/or surface agitation will enhance gas exchange with the surrounding air leading to a faster rate of equilibartion with the CO2 level in the surrounding air. I'd check that first .

A calcium reactor will lower pH and many have difficulty keeping pH above 8 when using them; typical effluent pH is around 6.5 to 6.9. There may also be impurities in some media products and constancy of dose can be a problem. I haven't taken mine off the shelf in about 8 or 9 years.

As of 10 July...

Alk = 8.4
Cal = 460 (I've already adjusted the dosing program to bring that down to 420)
SG = Do you mean specific gravity? That's 1.026

I've already added a couple of air stones in the sump to help with the gas exchange and skimmer is on next month's purchase list.

Maybe I'll get the skimmer installed a little sooner and see what that does to my pH levels. Not sure if that would lower it enough to start dosing the Alk part of the 2 part or not though.

 

[bertoni]

More aeration should bring the pH down if the tests are correct. The only way to have pH that high is to have a low concentration of carbon dioxide in the water. Usually, the cause of high pH episodes is overdosing a high-pH alkalinity supplement, like Kalk. They can be caused by photosynthesis combined with a lack of aeration. Those are the more likely issues, other than testing errors. Even with two kits reading the same level, I'm still suspicious. You could check for surface films on the water. They can reduce aeration quite a bit, although they are rare in practice.

 

[outssider]

under normal circumstances, 8.7 is practically impossible.....there is a testing problem

 

[Etoimos]

So here are my parameters as of this evening...

Alkalinity: 7
Ammonia: 0
Calcium: 460
Magnesium: 1100
Nitrate: 5
Nitrite: .1
ORP: 313
pH Probe @ 79.8°: 8.8
pH Test Kit: ???

I'll let you guys try and decide what reading this is...

 

[bertoni]

I don't see how the tank could be at 8.8 pH. I suspect bad calibration solutions or electrical interference. How are the animals doing?

 

[tmz]

I agree; I also have no idea what the Red Sea test is trying to say.

 

[wrott]

Could your rock or substrate be leaching Ca(OH)2?
Are you dosing Na2CO3 or NaHCO3?
I'd check pH w/ another meter, call lfs--they may have one.

 

[Etoimos]

I re-calibrated the pH probe this morning and for the past 30 mins it has been reading 8.06-8.07. That seems closer to what I would expect my tank to be sitting at. I'll leave it as is for half the day and then turn off the air stones to see if that changes anything.

I will be picking up another pH test Kit to triple check both the probe and that Rea Sea kit I have... that color is suspect to me.

If nothing else, I learned quite a bit from this thread, so thank you to everyone that replied.

 

[bertoni]

Okay, that range is quite reasonable.

 

[Etoimos]

Yeah, it's slowly dropped down to 8.01 over the course of the day.

 

[bertoni]

That change is small enough to be within reason.

 

[Etoimos]

Yeah, I thought so. It has climbed back up to 8.03 when I turned on more intense lighting for a bit. So it seems to be reading correctly now.

Thanks again for all the input on this thread everyone.