pH !!! Serious help needed !!!

[CoralHead]

QUICK! I am having a pH catastrophy! Any experienced help is appreciated. I have 2 tanks. BOTH usually run a pH of 7.85(night) - 8.00(day). I have ALWAYS had trouble getting those numbers up. Now here are parameters of my 225gal and equip.: READ BELOW ALL THIS DATA FOR THE REAL problem.

dKH - 11.2 (4.0 meq/L)
Mg (Magnesium) - 1240 - 1280 ppm
Ammonia - 0 ppm
Nitrite - 0 ppm
Nitrate - 0 - 5 ppm (trace, if any)
PO4 (Phosphate) - nil
SO2 (Silicate) - trace
Specific Gravity - 1.023

Ca reactor = Korallin (However, this usually lowers my pH by another 0.1, so I run it infrequently - lately). I drip Kalk when I am not using it. This helps elevate my pH.

I use RO/DI water from my tap source - 0 ppm TDS

ETSS downdraft skimmer (Lots of air exchange)

Currently using activated carbon, phosphate/silicate remover media (had problems with that a couple of weeks ago), and a dissolved organic removing media. All this is in my 30 gal sump.

I run a 57w UV sterilizer.

!!!!!! Everything listed is ONLY ON MY 225 gal REEF. !!!!!

My 80 gal FO Fish Only NO live rock. Is a C Urchin skimmer only. I have phosphate/silicate remover media in there too.

I have used copper in my 80 gal, so they are not interconnected. However, on the 15th of Feb. (Tues) I took 15 gal of water out of my 225 gal reef and used it in a water change on the 80 gal. I do not believe this is the source of my problem.

SO... HERE is the real issue at hand.

I woke up this morning to find BOTH tanks pH @ 7.45 - 7.50 !!! The parameters I listed above are current as of 1 hour ago (this morning after the pH problem was realized). What am I missing here? ? ? HELP, PLEASE! I don't want to add buffer in fear of elevating the KH any more than what it is. Would pH fall if dKH is too elevated? I have never heard of that. I use a AM PinPoint monitor for the pH. I thought it was at fault, so I used a titration/drop pH test kit and it corroberated the info. So, I do not believe the pH monitor is at fault here. I just calibrated it 2 weeks ago.

Would the off/on use of Ca reactor be at fault? But if it is, how does that explain the same issue with the 80 gal. with no Ca reactor?

I don't know how my water source could be at fault because it's the KH buffer in the tank, along with the Mg levels for the ionic ratios to balance.

Any quick, useful suggestions are DEEPLY appreciated.

I guess I am stumped in a slump!

[dougc]

Your alkalinity is a bit high, but I don't see how that would depress your pH, either. The kalk should raise your pH, but the amount added will be limited by your evaporation. You could blow a fan on your sump (or the tank) to increase evaporation. If you are running a calcium reactor, I would run kalk full time, because it will help compensate for the pH drop from the calcium reactor.

You seem to have double-checked the reading from your meter using a test kit. When was the last time you calibrated the pH meter? What kind of calibration buffers are you using? Check out Randy Farley-Holmes' article on reefkeeping.com on the inaccuracies of various brands of calibration buffers.

For a quick fix, you could use washing soda to bump up your pH. I'm not sure what it will do to your alk, though.

Another possibility for lowered pH is poor ventilation in the tank or sump area. Excessive co2 can diffuse into the water. I'm not sure how to test for that, but try opening a window in the room for a few hours. I say this lightly without knowing where you live or how cold it is outside.

I run a refugium lit 24/7 with macroalgaes, which helps limit the nighttime pH drop somewhat. Not a quick fix, but something to think about.

That's all the ideas I have for the moment. I'll let others chime in.

[CoralHead]

I know. It seems perilous!

Update: I dosed kalk (pretty good amount)...pH is at 7.84 currently. Initially, was at 7.99, but is falling again. I have a fan on the sump almost all the time. It helps with my MH lighting on the 225gal. I have tried an airstone on a glass of each tanks water and it actually depressed the pH further versus raising it. So, I don't think it's an oversaturation of CO2, but I know CO2 can do that.

-Calibration of pH monitor was 2 weeks ago

I do not have a refugium, but have read a bit on them. Was thinking of it, but I do not have enough information to make an informed decision. Any thoughts???

I am still 110% puzzled. Alsoam waiting for my LFS to open - for their thoughts. BUT please, any others are appreciated.

It is cold here. I am in Ohio, but the 225 gal is in my finished basement. I have opened the window from time to time. I'll do it again now & post any results.

dougc - any info on what type of macros are good to use??? Thanks in advance.

[CoralHead]

Your alkalinity is a bit high

Any ideas on lowering the pH, besides giving it time?

[dougc]

Some people use various forms of caulerpa, but I think the best algae is chaetomorpha. It looks like a coarse brillo (or a hairball). It doesn't attach to the substrate. It just kind of floats around, at least until it fills the refugium. I just rip out a few handfuls every week and throw it away. Ask around locally. You should be able to find someone that will give you some. I'm not even sure where mine came from, since I didn't purposefully buy it. There must have been a little of it mixed in with some other macros that I added. The chaeto has really taken over.

As far as lowering alkalinity, it is probably not high enough to cause immediate concern. Dosing kalk may be driving your alk higher, but it should also raise the pH, which is desirable. Some people run their alk this high all the time. I subscribe to the belief that conditions should be maintained as close to a real reef, which means an alk between 7 and 8. There are some reports that elevated alkalinity may be associated with STN/RTN events with acros.

To see if excess co2 is responsible for the low pH, you could try the aeration test suggested in this article. There is a lot of other information about pH there that may be useful.

[CoralHead]

To see if excess co2 is responsible for the low pH, you could try the aeration test suggested in this article. There is a lot of other information about pH there that may be useful.

I'll keep you posted. Great info.

[kevinpo]

Hello,
Often in closed basements CO2 builds up in the room and will lower the PH in your tank. PH can be easily raised without raising the alkalinity by adding sodium carbonate (sold as washing soda in the supermarket). You will have to keep dosing it regularly to maintain PH levels. Plants in a refugium will use CO2 and put off oxygen which will help to raise the PH. I have run 7.8-8.0 for more than 1 year without ill effects when using a calcium reactor. When I added plants on a reverse lighting cycle, and a Kalk reactor the PH rose to 8.15-8.3.

I didn't see a reading for calcium? You can lower your alkalinty by raising your calcium level (unless your calcium is already high).

HTH,
Kevin
PS: I you can't find any sodium carbonate PM me and I will send you some along with the label off the box. It is sold by Arm & Hammer.

[CoralHead]

kevinpo, thanks for the info. It was very insightful. My Ca is currently @ 470ppm. So, it's doing great.

Update: I think I found the source of my problem. Our furnace was out for 2 days until the repair could be made. It is a high efficient model which pulls in air from the outside. ALSO, my wife decided that we would heat the house with our gas fireplace in lieu of the furnace. 1 + 1 + too high of CO2 in our home. Hence, it drove our pH's down in both tanks which are in different rooms. The downdraft skimmers introduce high volumes of air and mixed 'er all up for the resulting drop. That also explains why my airstone in a cup of H2O experiment did not raise pH, but actually lowered it. I tried the same experiment outside with boosted pH as the result. I was just feeding the CO2 into the cup from the air pump. I want to thank everyone for the input. I am going to look into a refugium w/ macros for additional help. Thanks a bunch!

[Spick]

QUICK! I am having a pH catastrophy! Any experienced help is appreciated. I have 2 tanks. BOTH usually run a pH of 7.85(night) - 8.00(day). I have ALWAYS had trouble getting those numbers up. Now here are parameters of my 225gal and equip.: READ BELOW ALL THIS DATA FOR THE REAL problem.

....
Specific Gravity - 1.023
....

To me this is your main problem. It's like food, when something is sour you would think you would add sugar but actually salt lowers acidity. having your gravity at 1.023 is quite low for a reef keeper. From everything that i know one that mainly stands out is definitely keeping your gravity (salinity) at 1.024 minimum to 1.026 maximum.

When PH is low is means your water is getting more acidic. try rasing your salinity and watch your ph levels rise. Raise your salinity slowly and you should get better results. Hope this works for you!

NOw i am new to giving advise but this is something that definitely stands out for me. If someone can correct me please do, so i may be informed. But i am prety certain. Cheers