pH of 7.4-7.5

[nickkohrn]

I set up my tank about two weeks ago. I started with RODI water, dry rock, and some MarinePure ceramic media in a rear chamber. I then added my Instant Ocean Reef Crystals, which was two years old, to reach 1.025 SG. I let it run for a few more days before adding my Apex and Dr. Tim’s ONE and ONLY to start a fishless cycle. I calibrated my Apex and added some sand because I decided to not go bare-bottom. I have been getting alarms about my pH being 7.4 since my Apex has been installed (~ one week). I tested my pH with a test kit, and it confirmed what my Apex was reading. I chalked it up to being my salt. I went and bought some Red Sea Coral Pro salt yesterday, and I made saltwater that matched the 1.025 SG of my tank. I tested the water with my test kit, and the pH of the new water was 8.2. I had made ten gallons (twenty-gallon tank). Since the pH of the newly-made water was what I’m after, I did a 50% water change today. However, my pH has only risen to 7.5. I have verified this with my Apex and test kit.

Is this part of the cycling process? It seems low to me, even at this stage of the tank’s lifecycle.

 

[nickkohrn]

As I watch my Apex, the pH is dropping back down toward 7.4. I opened our large windows in the room where the tank is to see if that makes any difference. I have plenty of surface agitation, so there should be adequate gas exchange happening.

 

[FartyParty]

What is the system water volume? Have rock & Substrate type?

 

[hatfielj]

First, I wouldn't even worry about it right now. Your tank is practically lifeless at this point, so pH really doesn't matter. Eventually your pH will start to rise as the tank starts to have some photosynthesis happening. Also, this time of year everyone has lower than normal pH. It has something to do with indoor A/C in my opinion. My tank has been running 7.7-7.9 ever since we started running our A/C this year. Over the winter it runs 7.9-8.1.

I'm guessing that the new, dry rock has something to do with your especially low numbers. Once you get some algae growing in there, you'll see an improvement. Have you considered maybe getting a small piece of established live rock to place in your tank? IMO that would jump start things a lot faster than just using Dr. Tim's and give you a lot more biodiversity.

 

[nickkohrn]

Thanks so much for your insight and for some peace of mind!

The main reason that I have wanted to stay away from live rock is because I have such a small tank, so ordering any online would be pretty expensive for my use. Secondly, our LFS’ have some rock, but it’s either covered in bubble algae or Aiptasia, or the pieces are much larger than I could fit into my tank. I’m not opposed to using some live rock. I just need to find some locally. Maybe I will go look this evening.

 

[nickkohrn]

What is the system water volume? Have rock & Substrate type?

It’s a 20g AIO. I have some MarinePure in a rear chamber, about 15lbs of rock in the display, and about 1/2” of sand.

 

[Randy Holmes-Farley Verified Community Expert]

pH is determined mathematically by the carbonate alkalinity and the carbon dioxide level. Nothing else matters at all.

If the alk is normal or higher, then low pH (if its accurate) means excess CO2 in the water.

A water change is never a good way to deal with pH issues since the CO2 almost certainly is coming from your home air.

I suspect your measurement is somewhat inaccurate, and I wouldn't worry about it now. People measuring pH with controllers often have inaccurate pH measurement, possible due to electrical interference, or due to improper temperature correction/calibration issues.

I would no nothing at the moment, since I think it unlikely to be accurate.


This has more:

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

 

[nickkohrn]

pH is determined mathematically by the carbonate alkalinity and the carbon dioxide level. Nothing else matters at all.

If the alk is normal or higher, then low pH (if its accurate) means excess CO2 in the water.

A water change is never a good way to deal with pH issues since the CO2 almost certainly is coming from your home air.

I suspect your measurement is somewhat inaccurate, and I wouldn't worry about it now. People measuring pH with controllers often have inaccurate pH measurement, possible due to electrical interference, or due to improper temperature correction/calibration issues.

I would no nothing at the moment, since I think it unlikely to be accurate.


This has more:

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

Thank you for your insight and knowledge! I guess I have just been caught up in chasing the number rather than waiting it out.

 

[Randy Holmes-Farley Verified Community Expert]

Thank you for your insight and knowledge! I guess I have just been caught up in chasing the number rather than waiting it out.

It's fine to chase pH, you just need to know how to do it. No one has a problem when chasing pH properly (despite the mantra many people espouse to not chase it), it's only when they chase it incorrectly that they have an issue.

 

[fab]

It's fine to chase pH, you just need to know how to do it. No one has a problem when chasing pH properly (despite the mantra many people espouse to not chase it), it's only when they chase it incorrectly that they have an issue.

How do you do it, chasing pH properly.

 

[Randy Holmes-Farley Verified Community Expert]

How do you do it, chasing pH properly.

There are several good ways and several bad ones. Buffers from the lfs are bad ones.

Fresh air in your home, fresh air to a skimmer inlet, CO2 scrubber on skimmer inlet, and hydroxide-based additives when you need alkalinity are all good choices.

 

[hatfielj]

Thanks so much for your insight and for some peace of mind!

The main reason that I have wanted to stay away from live rock is because I have such a small tank, so ordering any online would be pretty expensive for my use. Secondly, our LFS’ have some rock, but it’s either covered in bubble algae or Aiptasia, or the pieces are much larger than I could fit into my tank. I’m not opposed to using some live rock. I just need to find some locally. Maybe I will go look this evening.

It can be tough to source good live rock these days. I too would be very picky about where I get it. For a small tank you don't need much though. Maybe talk to some local reefers in your area. I'm sure someone with an established tank could hook you up.

 

[beaslbob]

more plant live like macro algae will raise your ph by sucking out the co2. So that your lowest ph with macros will still be much higher then your before macro ph.

Besides from what I hear the cycling process results in lower pH until it is finished.

my .02

 

[NY_Caveman]

Nick, you may want to check out these forums or try a post there if you are looking for a small piece of live rock to seed the tank.

https://www.reef2reef.com/forums/ohio.554/

 

[nickkohrn]

Nick, you may want to check out these forums or try a post there if you are looking for a small piece of live rock to seed the tank.

https://www.reef2reef.com/forums/ohio.554/

Thanks for the recommendation! I will dig in this evening.

 

[nickkohrn]

I opened my windows for a while today, and my pH started to rise. It’s too hot to keep the windows open for long, though.