Question about pH levels

[TheBigDrewsky]

Hello,

Quick question....

Just bought a AC Jr and have the pH Monitor attached. It was calibrated at time of set up. Been up and running and doing very well over a week now.

Now that we can closely monitor the pH levels, we have noticed that when the lights are off, the pH drops to 7.7 or so, and when the lights are on the levels go as high as 8.1

We have a 45g tank, params are as follows:

NH3=0
NO2=0
NO3=<1
PO4=<.1
CA=400
Mg=1300
Kh=9

We are keeping assorted zoas, LPS, clam, sea fan, and now have about 11-13 SPS which are thriving and doing very very well. Livestock includes 2 true percs, juvenile hippo, 6-line, algae blenny and a pretty well stocked CUC.

So question is, is this an appropriate pH level for a tank of this size and its inhabitants? I read a lot of things where people try to keep pH levels between 8.1 and 8.3, but we have rarely, if ever gone above 8.1.

Thoughts?

I want to practice the old adage "if it isnt broke, dont fix it" but just want to be sure we newbies are doing any long term damage.

Thanks!

 

[afboundguy]

You are correct that a lot of people try to keep their pH around 8.1-8.3. It is also normal for a pH drop at night but IMO that is a little steep. I get about a .1 difference between night and day.

Couple of questions so to help troubleshoot. Do you keep the tank covered? If you keep it covered you might want to uncover it to get better oxygen exhange and this would help keep the pH up.

Do you have a sump? Again along the same lines as above, this would help with oxygen exhange. Also if you have a sump do you have a refugium? If you have a refugium you could do a reverse lighting schedule DT lights on fuge tanks off and vis-versa. This could help keep the pH up during the night time hours... Hope this helps...

 

[biggyclops]

are you using outside air for the skimmer? if not this will help some.. also Ph drops more at night than during the day.. when i got my ph probe i almost freaked when i saw it at night.. mostly because we test during the day where ph is the highest.. and rarely at night where you might notice it..

But from reading your question i think your ph is a little too low for night time.. 8.0 to 8.1 is fine.. so you might want to see if you can plumb some tubing from the outside to your skimmer.. anyone else?

 

[reverendmaynard]

You can use kalkwasser as a means of maintaining calcium and alkalinity as well as raising your ph. Dripping only at night will help keep the ph stable.

 

[marine mike]

+1 on the outside air for the skimmer and the kalk drip as a last resort. I have read (I think it was Randy's article) that ph can be considered safe down to about 7.8 or so in a reef and then it can pose a problem. I try to keep mine from 8.05 or so at night to 8.4 during the day or somewhere in between. I do drip Kalk as I have a calcium reactor running also, but with your setup, just the Kalk would probably help you not only with ph but with supplements of calcium/alkalinity also. If you choose to drip as stated before do it at night when the ph tends to drop. It is quite possible if your skimmer uses quite a bit of air that just the fresh air pull from the outside might do the trick for you. Good luck!

 

[biggyclops]

its is amazing if you track your ph and then use outside air!!! the first day i did it i didn't really notice a big difference.. it wasn't until that night... also i think with the cold dry air it helps pull more gunk out of the water..

 

[TheBigDrewsky]

Thanks for all the comments.... let me respond.....

This is a 45g pentagon... our first tank. We use a CPR BakPak skimmer and a CPR HOB Refugium. The tank is open although we use eggcrate over the top to prevent flying fish syndrome.

The BakPak skimmer has an external air hose which is open most of the way to increase bubble production. And with the top open, we should be getting good air exchange. The tank is in a very large open living/dining area with 18" ceilings. There is a ceiling fan which is always on and the ambient room temp is constantly 68-72 degrees.

I am not sure what all is involved in the mechanics of dripping kalk but it seems a lot of work to me for a 45g. But then, we do want to preserve and care for the corals and livestock we have invested in.

Is Kalk the only solution or would using pH buffer be more economical in the long run?

Thanks for your thoughts.

 

[afboundguy]

you could try to raise your alk a little (pH buffer) but it's already at 9dkh which is pretty good. You could try bumping it up to 10-12 range see if that helps a little...

 

[TheBigDrewsky]

Just a quick update. Since the last post, we have been just monitoring the pH levels and water parameters, also keenly observing the growth rate of the corals and well being of the livestock.

Observations:

The tank pH at night, without lights, gets as low as 7.7 or so and again, rarely if ever climbs to 8.0 even with our MH on during the day and early evening. Temps remain within the 79.3 to 80.3 range.

Ca levels range from 400-450
Mg levels 1200-1400
Kh levels from 9-10
PO4 is 0
Nitrate is 0

We only dose the tank with the CA part (of the 2-part) daily. Since our KH is already 10, we dont dose the alk at all.

We have noticed, believe it or not, some extraordinary growth of our SPS over the past month. LPS are doing very well too. Livestock seems to be flourishing, good eating, etc.

In addition, we do have an overgrowth, I would guess, of green algae which may be because we used to overfeed phtyofeast. Since about a week ago, we stopped feeding phytofeast, increased our snail population, and have begun to see a small decline in the algae, but imagine this will still take a few weeks to really decline. (We plan on more snails tomorrow). Unless of course, we cut back on the MHs for a few days. (Thoughts?)

So, let me ask again....with everything the way it stands now...should we work on boosting the pH to 8.1 to 8.3? Or....Leave well enough alone and be thankful?

If we need to boost pH, we want to do this easily (would prefer to use a pH buffer rather than drip kalk). If this seems to be a good option, anyone recommend particular products? Dosing schedules or parameters?

Thanks in advance!

Andrew

 

[Casino]

If your ALk is stable where it is now I see no need to worry about your PH. As long as your ALK is stable you will be fine. None of the PH boosters will maintain the PH. It will only raise it for a few moments and then you will watch it fall again and all you would of done is increase your ALK. The only way to increase the PH or atleast put it up to normal is to have a refugium in reverse light, open the windows in your house as you might have excess CO2 in the room and a few others..read this Ph causes and cures

 

[reefkeeper2]

A pH buffer is not the way to go. You will get a yo yo effect. There are a couple of reliable ways to solve your problem. Usually people use more than just one of these methods. First would be to find a way to run some airline tubing from outside to your skimmer air intake. The next is to use kalkwater. If you can't do either of these, you could turn down your reactor a little (less CO2) and supplement your Ca and alk if you need to with a two part solution. This might be your best option. It might be enough to bump your pH to an acceptable nightime range. Another trick you can try is to add on another chamber to your reactor filled with more media. DIY reactors are easy to make. I have 2 of them and it helped a lot. Another method some people use is to have a refugium full of macro algae on a reverse light cycle than your tank.
Even in a large open room during the winter the CO2 levels in the home can climb pretty high causing your pH to decrease. Right now your night time pH is too low, and if something should happen that brings it even lower, you could lose some fish overnight.

 

[TheBigDrewsky]

A pH buffer is not the way to go. You will get a yo yo effect. There are a couple of reliable ways to solve your problem. Usually people use more than just one of these methods. First would be to find a way to run some airline tubing from outside to your skimmer air intake. The next is to use kalkwater. If you can't do either of these, you could turn down your reactor a little (less CO2) and supplement your Ca and alk if you need to with a two part solution. This might be your best option. It might be enough to bump your pH to an acceptable nightime range. Another trick you can try is to add on another chamber to your reactor filled with more media. DIY reactors are easy to make. I have 2 of them and it helped a lot. Another method some people use is to have a refugium full of macro algae on a reverse light cycle than your tank.
Even in a large open room during the winter the CO2 levels in the home can climb pretty high causing your pH to decrease. Right now your night time pH is too low, and if something should happen that brings it even lower, you could lose some fish overnight.

Questions....

"run air line tubing from outside your skimmer air intake."

We use a CPR BakPak Skimmer. Attached to the skimmer is an airline tubing with a valve at the top - which when opened more fully produces more skimmate. Is this what you are suggesting? Open the valve more fully which pulls more air in, or are you suggesting we run some tubing form the outlet opening and draw air in from the outside of the house?

Thanks!

Andrew

 

[jrmx635]

ph sways

forget about the ph.
It will never stay at one number.
night time drop is normal even with a refugium.
I haven't checked ph in years,just maintain mag,cal,and alk as priority and you will be fine.
Refugiums help with night drops but unless you have a big one with a ton of algea,you'll still get a drop.
I am going to use the ph on my aquacontroller for the calcium reactor only.Because with a calcium reactor the ph of the reactor water is important.

 

[afboundguy]

Questions....

"run air line tubing from outside your skimmer air intake."

It means taking that intake tube from the BakPak and running it so it sucks outside air. In the winter with everybody always closing their windows there is a lot more C02 in the house which naturally lowerd pH in our tanks. One way to combat this in the winter time is to extend the intake hose and run it to the outside so it sucks in fresh air.

 

[reefkeeper2]

That's correct. The idea is not more air, but air from outside. The outside air does not have the high concentration of CO2 that your tank water (or winter time house air) does. When the fresh air mixes with your tank water in the skimmer, the difference helps drive the CO2 out of the water to reach equilibrium with the air. The result is the CO2 concentration in your tank water will drop and your pH will rise.
I don't completely agree with the comment to forget about your pH. If the swing is a minor one, then you don't have to be concerned. The goal to strive for with your reef is consistancy and stability. You want to minimize or eliminate daily parameter swings as best you can. This applies to all parameters like temp, salinity, etc. The more stable they are, the better your reef will be. Further, there is now anecdotal evidence that high CO levels (low pH) can trigger and sustain red cyano outbreaks.

 

[marine mike]

I concur with those posts saying do not forget about your ph. there are some things more sensitive to ph than others, but stability is the key and if you are in range and have a strange event, you are much less likely to lose anything than if you are borderline and then have the same strange event. I would say try the outside air if you can do it easily. I just started it a week or so ago and have noticed that it has reduced my nightly swing in ph. I now have a smaller range day to night than before, which IMO is a good thing for my tank. If you are running down to 7.7 at night it is not a really dangerous thing, but borderline. If you then have an issue that causes a drop of .2 or .3 more, you have an issue. Rather see you in the 8.0 to 8.3 range night to day, then you have some wiggle room. Running a calcium reactor with any load you will eventually need to compensate for ph drops IMO or you will have an issue.

 

[Randy Holmes-Farley]

FWIW, many hard corals have a much harder time calcifying and grow a lot slower as the pH drops. That is a clear stressor, IMO.

That is one of the reasons that scientists are so worried about reefs as CO2 levels in the atmosphere rise.


IMO, folks should try very hard to keep the pH above 7.8, and above 8.0 is better yet.

I discuss these issues here:

Low pH: Causes and Cures
http://reefkeeping.com/issues/2004-09/rhf/index.htm

The "How To" Guide to Reef Aquarium Chemistry for Beginners, Part 3: pH
http://reefkeeping.com/issues/2007-05/rhf/index.php

 

[TheBigDrewsky]

Hey,

Thanks to everyone for their thoughts and opinions. We will try to find a way to bring in some outside air. The tank is about 12 feet from the nearest window or door. I guess we could run some air tubing along the baseboards and out to the window.

Interesting that Reefkeeper mentioned Cyano with low pH. We just noticed some. Spent the afternoon getting rid of it. Will definitely look at how to increase the outside air without having to cool off the whole house at the same time....grin.

Thanks again for everyone's thoughts. Will keep you updated, and thanks again for all the references.

Andrew