Ph Fluctuation

[rongy]

Hi reefers, looking to get some suggestions on my Ph. My Ph sometimes drops all the way down to 7.7 or lower before light is on (light schedule 2-11pm), and the high is about 8.2. It averages around 8. Corals seem to be happy, but I always heard that higher ph will boost growth.

Is it worth increasing the ph? A few options I have in mind:
1. Drill dry wall behind the tank and get air there (not sure if it will boost the ph, but that’s the best I can do to get good air outside of the room)
2. Get CO2 Scrubber
3. Dosing Kalkwasser (currently dosing two parts)

Thoughts?

 

[MnFish1]

First- unless you have verification that the pH is 7.7 - I would ignore it. Second - even if it it 7.7 - its likely due to CO2 levels in your house at various times of the day - OR - CO2 levels in the dark.

To specifically answer you - not sure how much surface/ other flow you have - but - drilling shouldn't help. A Co2 scrubber should - and Dosing Kalkwasser in your ATO should as well. However - in general if your corals, etc look good - I would not worry.

 

[rongy]

First- unless you have verification that the pH is 7.7 - I would ignore it. Second - even if it it 7.7 - its likely due to CO2 levels in your house at various times of the day - OR - CO2 levels in the dark.

To specifically answer you - not sure how much surface/ other flow you have - but - drilling shouldn't help. A Co2 scrubber should - and Dosing Kalkwasser in your ATO should as well. However - in general if your corals, etc look good - I would not worry.

You’re right, the Ph drop is likely caused by CO2 level. It goes below 7.8 a few times a week and lasts about an hour. I just calibrate my probe. Should I be concerned about those drops on ph?

 

[MnFish1]

You’re right, the Ph drop is likely caused by CO2 level. It goes below 7.8 a few times a week and lasts about an hour. I just calibrate my probe. Should I be concerned about those drops on ph?

I would not be worried - as long as your tank looks good (the way you want it to) - a CO2 scrubber would be an option. if you have a skimmer

 

[Pistondog]

Running a line outside for your skimmer would help if practical.
Those are not bad numbers.

 

[MnFish1]

You’re right, the Ph drop is likely caused by CO2 level. It goes below 7.8 a few times a week and lasts about an hour. I just calibrate my probe. Should I be concerned about those drops on ph?

PS you could also do a cheato reactor - that runs at night - which will tend to reduce Co2 - increase pH

 

[mattdg]

You should really be paying attention to PH trends rather than a few drops. True for most things in reefing. If you want to trend higher, maybe supplement with Kalkwasser or open windows to clear CO2 during the periods where you are observing the steepest drops. The PH scale is logarithmic, so even a slight improvement in average PH, will do a heck of a lot for overall coral health.

 

[Steve2020]

I agree with @MnFish1. Drilling a whole to bring in outside air does not give you any significant increase in ph. At least it didn't on my tank but it did go up a little. I tested just running outside air even going to a CO2 scrubber then to the skimmer and I did not see the increase I was expecting compared to the other test I ran on my tank. Here is the thread.

My Chart Data Showing ph Trends During Different Test Conditions

There seems to be a lot of post's lately about ph, CO2 scrubbers and skimmer recirc setups so I decided to collect some ph data for different scenarios. The data emphasizes more towards tends and not so much the actual ph values. My tank and parameters: LPS and Softies. 285gal total water volume...

www.reef2reef.com

 

[Randy Holmes-Farley Verified Community Expert]

I agree with @MnFish1. Drilling a whole to bring in outside air does not give you any significant increase in ph. At least it didn't on my tank but it did go up a little.

The effect of outside air, just like the effect of other means like a scrubber, will vary depending on how much tank top aeration there is relative to skimmer aeration. For some folks it is a no cost answer that works well enough.

 

[exnisstech]

1. Drill dry wall behind the tank and get air there (not sure if it will boost the ph, but that’s the best I can do to get good air outside of the room)

First of I'll say I don't fret over pH. Typically I never even test (I have no controllers or monitors). But after all the recent concern being posted about pH I decided to dust off my Hanna tester and see where I'm at. I have 3 tanks running. They are all pretty consistent around 8.3. All tanks run chaeto on a reverse light cycle. Co2 is pretty low in the house as it's open as much as possible. I did discover that the tank in our bedroom drops to 7.9 over night with 2 adults and 2 dogs breathing in the room. I ran an airline from the skimmer intake into our attic which is isolated from the living quarters but vented to the outside. After adding the fresh air to the intake pH is 8.3 in the morning. Adding the airline definitely made a difference for me. I wouldn't have bothered spending money on a scrubber or something as 7.9 at night and 8.3 during they day is fine IMO but I'll take a free bump if I can get it. I ran the air line temporarily to see if it would even work before drilling into the attic. Maybe you could run one outside temporarily and see if it makes a difference in your situation

 

[MnFish1]

The effect of outside air, just like the effect of other means like a scrubber, will vary depending on how much tank top aeration there is relative to skimmer aeration. For some folks it is a no cost answer that works well enough.

I (think) I misread the post - I was under the impression he was just going to drill the dry-wall behind the tank, as compared to bringing in outside air. Agree completely that if you can bring in outside air - it can be a (sometimes big) help

 

[jda]

The up/down is from photosynthesis bump. If you want to stop the up/down, then a reverse light cycle fuge is best.

As said above, co2 in your home is the main reason that pH can lower. It is easy to fix and does not even have to warm or cool you home, but for some reason people just don't want to do it or think that they are going to get icicles on their light fixtures by opening a few windows for one minute a day... or the heating or AC cost is too much but they spend hundreds on buying and shipping a reactor and media to save a few pennies on natural gas. If your indoor co2 is over 600-700, then it is affecting the pH in your tank... period... and even if you are using an outside air line, co2 scrubber or kalk, fresh air can still help a lot. Closer to 400 is the best.

Edit: also, if the co2 is high enough to be messing with your tank pH too much, it is messing with you too, whether you know it or not. Fresh air is not just good for the tank.

 

[MnFish1]

The up/down is from photosynthesis bump. If you want to stop the up/down, then a reverse light cycle fuge is best.

As said above, co2 in your home is the main reason that pH can lower. It is easy to fix and does not even have to warm or cool you home, but for some reason people just don't want to do it or think that they are going to get icicles on their light fixtures by opening a few windows for one minute a day... or the heating or AC cost is too much but they spend hundreds on buying and shipping a reactor and media to save a few pennies on natural gas. If your indoor co2 is over 600-700, then it is affecting the pH in your tank... period... and even if you are using an outside air line, co2 scrubber or kalk, fresh air can still help a lot. Closer to 400 is the best.

The new bath fans can also be quite powerful with less energy use. leaving one on (if you have one close to the tank) can also help considerably.

 

[DeputyDog95]

For those that say, "Don't worry about pH"... Immediately disregard their posts, they have no idea what they're talking about

All kidding aside, will a lowish (sub 8) pH kill your corals? Nope. Will a much higher pH (>8.3) make your coral growth explode? Yep. So, while not required, you will have significantly better results with your pH running at the higher end of the range.

I have a fairly crowded and established SPS tank, and have tried every trick there is to boost SPS growth. Nothing made a difference like boosting pH did.

Now I do the following:
Soda ash for Alk in the 2-part
Dosing Kalk in the sump 24/7 (less during the day, more at night)
Refugium on a reverse light cycle
CO2 scrubber on a solenoid (non recirc, tried the recirc for months and the moisture build up is not worth the hassle)
ERV install

My occupied office C02 is now around 650. Without the ERV is was around 1300. I have one more higher fan setting to try and hopefully that will get me closer to the unoccupied office numbers (425).

The SPS growth in my new range (old was 7.9 to 8.1) is bonkers. The established colonies grow so quickly now I have resorted to pruning.

Even though I have the scrubber on a solenoid that switches between scrubber and ambient air, I still have a hard time making it consistent on the weekends as compared to weekdays when the office is unoccupied and the CO2 levels drop to 425. The pH gets up to 8.6 on weekends, but the corals don't seem to mind. Yeah, I'm that guy that bought a C02 monitor that datalogs LoL

Yeah, you have an amazing coral tank without fooling with the pH and running about 8, I've seen plenty. But if you want to see things grow at a rate where you can see weekly differences, put your money/equipment in boosting pH. BRS has some tests as well, which is what spiked my interest.

One last thing... I started playing with the pH 4 or 5 months ago. Ish. I was dosing around 75ml/day of BRS 2-part. I'm now dosing 325ml/day of 2-part, and dosing Kalk. And if I could dose more Kalk to save on 2-part, I would, but I'm already pretty close to matching my evaporation.