Low PH worry

afamousjohnson · Dec 5, 2014

So I have had my ph dipping pretty low recently. Been going on for a month or so now. I run a cal rx so a lower ph is expected but now its super low.
It generally runs around 7.8-8 but has been dropping down and often 7.5-7.6. at the end of my dark cycle it can even hit 7.4
I have moved the air line to the skimmer into a different room with windows light etc and it helped for a bit but now back to low. Have the seachem ph buffer and use but it only raises it temperarily and than back down.
Run seperate light cycles between display and sump.
What am I missing here, is there something else I can do? I haven't calibrated the ph probe off apex since the problem started but calibrated not long ago. I will be calibrating tho cause could easily be my problem??
Havent really noticed any ill effect with the tank from it except with some zoas acting up or going away - not all of them tho just some?

I have heard peeps that ran into a 7.4 and lower ph running into all kinds of trouble due to it. Should I be a lot more worried than I am at 7.5?

thanks for any input

Randy Holmes-Farley · Dec 5, 2014

If the pH 7.4 is real, it is a significant concern, IMO, as aragonite skeletons can slowly dissolve at that pH.

When was the last time you calibrated the pH probe?

A reasonable number of people use limewater (kalkwasser) along with a CaCO3/CO2 reactor for purposes of boosting the pH. Forget the buffer as that is not a good way.

afamousjohnson · Dec 5, 2014

Calibrated few months back when i was having reactor issues. I have some kalk in the garage but have never used. I will calibrate 1st and move to that if needed.
Best to run with ato? If you dont have a drip system set up?

Also our lfs here dont carry ph probe cal fluid?? Dont ask me why.lol but it is north cali so all the grow shops sell 4 and 7 cal fluid. Do u think i will be okay calibrating on the low spectrum of the scale rather than 7 and 10?

Randy Holmes-Farley · Dec 5, 2014

It is OK to calibrate at pH 4 and 7 if the fluids are good.

How fast does your ATO deliver water? The concern is that some deliver a lot in a short period of time, possibly boosting pH too high where it is dosing.

jayhawk · Dec 5, 2014

What is your Alkalinity, Calcium, Magnesium, and salinity? Although the cal reactor may be lowering the ph, you need to have stability. If the four aforementioned parameters are off, that could be the problem. I learned long ago to not chase ph. Ph is a direct result of stability. Oxygen plays a part in this as well. I would check the parameters....

afamousjohnson · Dec 5, 2014

Ill do some tests today n update but alk was last at 155 cal 460 mag 1250 sg 1.026
Ya i have never chased ph either - just let it do its thing and dont really worry to much in the low 7.8 spectrum but this 7.4 business has me jumpy.lol

afamousjohnson · Dec 5, 2014

Run the tunze ato so it pushes power on topping off. Thats the same question i was thinking. Guess i could diy a drip box and get it dripping all day or where i find i need it.?.

UK_Pete · Dec 5, 2014

I've got similar woes but when I did the aerate a cup of water test, I realised I had high CO2. And investigating the type of house and occupancy, it seems indoor CO2 levels of 1000ppm and higher are common in some houses. This time of year windows get closed more. Randy has pointed me towards limewater too, but also said another couple of things might work. Theres another thread https://www.reef2reef.com/forums/re...w-required-keep-carbon-dioxide-down-tank.html where hes commented on the idea of having a scrubber in the tank hood to remove CO2 from the air in the hood, which I might try myself. Kalk or sodium hydroxide with a dosing pump seems the simplest though.

afamousjohnson · Dec 5, 2014

Nice - thanks for the link.

calibrated probe - 1st round went to double check at the end and it read 3.85 on the 4.01 solution so I redid calibration and that round got the 7.00 and 3.99 so called it good there. Put it back in and it was off - still low tho
78.5 temp ph - 7.41 was previous reading
after calibrating at same temp ph reads 7.67 big difference.lol will still be looking into the limewater.

tigerdragon · Dec 5, 2014

I thought i gave you a 7.0 and 10.0 cal fluid? Are you on an apex? What is your average according to that?

Randy Holmes-Farley · Dec 5, 2014

jayhawk said:
What is your Alkalinity, Calcium, Magnesium, and salinity? Although the cal reactor may be lowering the ph, you need to have stability. If the four aforementioned parameters are off, that could be the problem. I learned long ago to not chase ph. Ph is a direct result of stability. Oxygen plays a part in this as well. I would check the parameters....

pH is determined by CO2 and alkalinity only. If you know those two, you can calculate pH mathematically.

Diesel · Dec 5, 2014

Scientific explanation says pH is the acid/alkaline balance.

Translated into a language those of us without the Ph D can understand, pH level refers to the amount of acid and alkaline contained inside the water.
If the environment is too acidic, that means the corals will not attract enough hydrogen, while an environment that is too alkaline will attract too much hydrogen.
An environment that continually fluctuates from one extreme on the pH scale to the other is unhealthy for the corals.
Hydrogen is one of four elements any living corals needs to survive.
Without hydrogen, the corals would wilt and not be able to take in nutrients.
Because the corals contains hydrogen, it continues to absorb hydrogen through the water via a process called osmosis.
This hydrogen-osmosis cycle is what keeps the nutrients traveling from the water into the corals.
The level of pH is measured on a scale of 0 to 14 with 0 representing the highest concentration of acid and 14 representative of the most alkaline.
Seven is the magic figure for pH because it means that there is a balance of acid and alkaline in the solution and is often referred to as pH neutral.
In our reef systems we looking at 7.8/8.3