Large pH fluctuations

[Bacchus]

Hello all. I have a 55g reef with LED, protein skimmer, refugium, and berlin sump. All parameters seem great although Ca is somewhat low. . .but my pH goes up to around 8.52 when I turn the lights off at night (9 pm) and down to 8.11 when I turn the lights on (10 am). I've been reluctant to use a CA/buffer combo since my pH increases significantly at night. Any suggestions on how to reduce the pH variability?

 

[extremecoral]

If your CA is low there are two things take into consideration. Heavy livestock(SPS mostly the case if you have them) or low on Magnesium level. If your CA levels are low use ‘Turbo Ca’ to bring the Ca level up to desired levels. Do NOT use a 2 partbuffer or anything that is going to boost dKH when doing so. You only want to add a CA booster. If you have a 2 part buffer only use the CA boosting part on the tank to bring up CA ONLY.

I also use the Seachem Marine Ph buffer. If you accidentally overdosed it. I will only stay at 8.3 level, BUT on the down side it boosts the Alk level alot. I don't know what kind of additives you use.

 

[kpiotrowski]

what is your alkalinty? what is the light cycle on the fuge? if it is on a night cycle as it should be then I would guess your alk is low and when you raise the alk you should less of a swing. ph 8.5 is not alarming! the swing is what you should be concerned about. also is your ph test/monitor reliable?

 

[trido]

Ive never heard of someone's Ph going up at night when the lights are off. Never.
Ph drops when the lights go off due to lack of Photosynthesis even if someone has a refugium. A refugium only helps the Ph swing to be less significant.

Are you using a test kit or a controller? If your getting these readings from a controller I'd suggest isolating the Ph probe wiring from the rest of the tank wiring. The reason I say that is that the probe's electrical current it ran with millivolts and can easily be manipulated with the EMF from any 120 volt wires near it.

If It's a test kit, I would quit testing twice a day. IME a tank with a Ph that high is very rare and usually only caused from dosing kalk or other DKH buffers.

 

[Bacchus]

I get my readings from a probe reading. It was recently compared to an API test kit. I use B-Ion 2 part solution and just took the advice of just adding the CA part. My refugium is rated for a 120g tank (mine is 55g). I wonder if my refugium light is insufficient. I think it's a 24w cf. I'll try alkaline adjustments as previously suggested but as of now, I still get a .40 ph drop from 9 at night to 8 in the morning.

 

[kpiotrowski]

you never stated your Ca levels, or alk levels. why do you want to add calcium? what affect do you think it will have? again do you run your fuge light at night? if so there is much to consider here and number one is don't bother with adding calcium when there is more going on here.

how big is your fuge, what lights are on it, how much macros, whats in the display tank for livestock, what are your nitrates, temp day and night, is your house more open to outside air in the evening and night and closed during the day?

I would test alk, cheap api test kit is fine, and try running fuge 24 hours and see what it does.

if you are overstocked there may be a consideration of o2 deprivation going on here and when your fuge is on and night its sucking up the co2 and giving off o2 raising ph....this is where I wonder if your alk is low becuase of the degree of swing.

 

[Bacchus]

Ca is around 400 which I'm not concerned with. 5 community fish, 60 lbs of, some hard and soft coral. Don't remember the volume or refugium but it's an eschopps r100.

 

[Tuku4u]

Just re-read your post, and realized you said your PH drops that much when your display tank lights go out at night. As far as your PH dropping at night, it seems to be a normal thing...at least in my opinion. My PH drops from 8.5 to around 8.1-8.2 over night but once the lights come back on it goes right back to where it should be. I did have a slight issue with my PH mainting during the day but it was due to low alk. I started dosing alk and got levels normal and now everything seems to be doing fantastic, even with the fluctuation of PH from night to day.

 

[kpiotrowski]

Ca is around 400 which I'm not concerned with. 5 community fish, 60 lbs of, some hard and soft coral. Don't remember the volume or refugium but it's an eschopps r100.

all of these questions I asked were not random, they were very specific to the problem......you never stated your Ca levels, or alk levels. why do you want to add calcium? what affect do you think it will have? again do you run your fuge light at night? if so there is much to consider here and number one is don't bother with adding calcium when there is more going on here.

how big is your fuge, what lights are on it, how much macros, whats in the display tank for livestock, what are your nitrates, temp day and night, is your house more open to outside air in the evening and night and closed during the day?

I would test alk, cheap api test kit is fine, and try running fuge 24 hours and see what it does.

if you are overstocked there may be a consideration of o2 deprivation going on here and when your fuge is on and night its sucking up the co2 and giving off o2 raising ph....this is where I wonder if your alk is low becuase of the degree of swing.

you can take all the "pot shots" at the problem you want, like "addding calcium" but the answer is to truly understand the science of what is going on. anyone that can truly help you will Need the above stated question answered more specificaly to help you any further.

 

[kpiotrowski]

Just re-read your post, and realized you said your PH drops that much when your display tank lights go out at night. As far as your PH dropping at night, it seems to be a normal thing...at least in my opinion. My PH drops from 8.5 to around 8.1-8.2 over night but once the lights come back on it goes right back to where it should be. I did have a slight issue with my PH mainting during the day but it was due to low alk. I started dosing alk and got levels normal and now everything seems to be doing fantastic, even with the fluctuation of PH from night to day.

he said ph goes UP at night is what is perplexing.

 

[Tuku4u]

but my pH goes up to around 8.52 when I turn the lights off at night (9 pm) and down to 8.11 when I turn the lights on (10 am)

Thats what I originally thought he meant when I first read it kpiotrowski, but reading over it again seems like he meant that his ph is at 8.52 when the lights go out, and then 8.1 when they come back on.

 

[Solov]

It looks like your Alk is fine (or slightly high) so stop dosing it until high pH stops going above 8.4. Run refugium on reverse cycle (light at night) if you don't already do so. Check Mg and make sure it's at 1300-1350 (check weekly to estimate consumption and dose accordingly). Alk + Mag at good levels should bring your pH swing down (along with oxygen at night from fuge).