Ph low

[Alwmh4]

I have a 17ga nano reef tank. All chemistry seems to be fine with the exception of ph which is hanging at 7.8. My buffer puts the water at 8.4 but once in the tank, it drops. I have a skimmer and air stone in the tank so it's probably not a co2 issue. Any suggestions? All inhabitants seem to be doing well but I would like ph at 8.2 as that is within recommended parameters.

 

[Eienna]

My pH was always at 7.8....
It doesn't seem to be a problem as long as it's stable and the other params are in line.

 

[Adam Baggett]

Couple of things. 1. With the lower pH is everything doing OK? If yes don't worry about it. 2. If the answer is no, and do you have an Auto Topoff? If yes then you can use kalkwasser in your ATO. I use it because my low pH causes issues.

 

[Alwmh4]

Yes everything seems to be doing ok. I use a two part buffer and when I add ph increaser nothing changes. I've added 15ml per day for two days. I don't like just dosing a tank all the time. I think it leads to spikes which are bad esp for nano. I don't have ato either

 

[pickupman66]

Stop dosing for your ph. What is your alk? This may be part of the cause. Is your pH swinging daily in large span?

Low ph is caused in part from higher co2 concentrations. open a window and see if it goes up. How are you measuring ph?

Fwiw there are many very successful tanks in that ph range. When you get lower however sps will have a more difficult time with calcification.

There are some great threads lately involving Randy Holmes Farley that you should read. Please check them out before pouring ph raising products in your tank.

 

[beaslbob]

First of all be sure you measure pH just before lights out.

Add some macro algaes to suck out the co2.

then use the diy 2 part to get alk in line. Or just simply add some baking soda to alk up to 8-10 dkh

my .02

 

[Randy Holmes-Farley Verified Community Expert]

I have a skimmer and air stone in the tank so it's probably not a co2 issue. Any suggestions?

That is likely because your home air has excess CO2 in it.

Low pH is ALWAYS due to excess CO2 somehow, assuming the alkalinity is not excessively low.


As mentioned, stop adding buuffers. They are rarely a good way to deal with low pH, and pH 7.8 is OK.

Have you measured alkalinity? High alkalinity from adding too much buffer may be a bigger problem than low pH.

As to recommended parameters, my recommendations given here are pH 7.8 to 8.5:

https://www.reef2reef.com/forums/re...-coral-reef-aquarium-randy-holmes-farley.html

 

[Alwmh4]

Yea I stopped dosing after trying 2 days. I don't believe in dosing. My kh is around 190ppm. I'm routinely using kent marine nano 2 part buffer only when mixing water. All I have right now are soft corals (Xenia, richordia, zoos). The Xenia is a weed it's doing so well. Richordias are ok. Zoos are doing ok tho they did suffer a while due to a few giant bristleworms that I have now taken care of. It seems to be improving quite well. I have skimmer and air stone going as well as a filter for a 70 ga tank even tho mine is a 17 ga.

I'm guessing that's all I can do and that it's nothing to stress over.

Tests I'm using are API reef master and saltwater kits

 

[Adam Baggett]

Does your skimmer have an air intake on top. I saw a trick once where an airline tube was attached to the air inlet and the other end was outside.

 

[Randy Holmes-Farley Verified Community Expert]

Yea I stopped dosing after trying 2 days. I don't believe in dosing. My kh is around 190ppm. I'm routinely using kent marine nano 2 part buffer only when mixing water. All I have right now are soft corals (Xenia, richordia, zoos). The Xenia is a weed it's doing so well. Richordias are ok. Zoos are doing ok tho they did suffer a while due to a few giant bristleworms that I have now taken care of. It seems to be improving quite well. I have skimmer and air stone going as well as a filter for a 70 ga tank even tho mine is a 17 ga.

I'm guessing that's all I can do and that it's nothing to stress over.

Tests I'm using are API reef master and saltwater kits

OK, so don't use any more buffers since alkalinity is already about as high as you'd want it.

If you choose to not dose limewater (kalwkasser) to supply calcium and alkalinity (and boost pH), the only way to raise pH is to either bring more fresh air to the tank (open windows or bring an outside air line to skimmer inlet, for example), or to run the skimmer inlet air through a CO2 scrubber.

If pH 7.8 is about as low as it gets in the early AM, then I wouldn't bother to take any drastic actions.

Also, pH test kits are often inaccurate and sometimes read low when old. I would suggest a pH meter, if you want to monitor pH.

 

[pickupman66]

Wow. I said his name and he shows up! So glad to have you around here Randy. the 190PPM is about 10.64 dKh and is on the higher end but not unacceptable. I like mine around 175ppm.

given everything stated, my bet is on excess CO2 in the house. open a window and let some fresh air in and see what it does. mine spiked considerably when I did this. Like the tank getting a breath of Fresh air.

 

[currentking]

my tanks PH sits at about 7.85 and when I open a window it jumps to 8.15 within about 30 minutes or so. alk is at 9.0 and cal is at 400. is that too large of a swing?

 

[Alwmh4]

Ok I'll research limewater and co2 scrubber. My tank is in the basement. I did this for light reasons. I'll open the door for a little while and see
If that changes.

I have to say I'm scared to change to limewater. Just have a fear I'll kill everything by tilting chemistry or something causing done cascade effect that I'm unaware of. If I'm understanding you correctly, you don't add buffer at all when mixing water for water change correct? Only limewater?

 

[Randy Holmes-Farley Verified Community Expert]

Ok I'll research limewater and co2 scrubber. My tank is in the basement. I did this for light reasons. I'll open the door for a little while and see
If that changes.

I have to say I'm scared to change to limewater. Just have a fear I'll kill everything by tilting chemistry or something causing done cascade effect that I'm unaware of. If I'm understanding you correctly, you don't add buffer at all when mixing water for water change correct? Only limewater?

For a water change, you mix nothing except water and salt mix. Don't add any supplement into that unless you have a good reason why.

For top off water, you can use just pure fresh water, or, as I do, use limewater (kalkwasser). It is the only calcium and alkalinity supplement I've used for 19 years.

These may help:

Low pH: Causes and Cures by Randy Holmes-Farley - Reefkeeping.com

The “How To” Guide to Reef Aquarium Chemistry for Beginners Part 3: pH by Randy Holmes-Farley - Reefkeeping.com

What Your Grandmother Never Told You About Lime by Randy Holmes-Farley - Reefkeeping.com

 

[Alwmh4]

Thank you!

 

[Alwmh4]

Any suggestions on which co2 scrubber and where to purchase? I have a reef octopus hang on skimmer

 

[Randy Holmes-Farley Verified Community Expert]

Any suggestions on which co2 scrubber and where to purchase? I have a reef octopus hang on skimmer

I don't have a brand I recommend. Some people make DIY scrubbers.

The media can get pricey in the long term.

 

[Randy Holmes-Farley Verified Community Expert]

Wow. I said his name and he shows up! So glad to have you around here Randy. .

Thanks!

Happy Reefing.

 

[beaslbob]

I know I'm kinda odd man out on this but I still say adding macro (or other) algae so the tank becomes a net consumer of co2 and source of oxygen each 24 hour period is the simplist and best solution.

With alk up above some value like 6-7 dkh the nightly ph drop is minimial.

And in my experience the lowest pH with macro algae (just before lights on) was still much higher (7.9) then the hignest yet more constant ph (7.6 (really low I know)).

even with a large nightly ph drop (8.4-7.9 api high range test kit) the tank seemed to thrive even with a heavy bioload and feeding.

When I started the diy two part and got alk up to over 8dkh the pH only dropped down to 8.2 or so.

With my limited experience I'm not aware of any fish or invert that does not do better with less co2 and more oxygen in the tank.

But that's just my experience which is worth at most.


.02

 

[Randy Holmes-Farley Verified Community Expert]

Macroalgae can certainly help, especially when lit at night.