Low pH and High kh - Add Baking Soda?

[murphy]

I have been batteling a low ph around 8.0 (dips to 7.9 at night), and a high kh around 13-14 for the past month. Cannot seem to get it right. Anything I seem to use fixes one and offsets the other. I have read so much information and probably more confused than educated now. Someone told me to just simply add Baking Soda and your ph will rise, w/o affecting your kh. But I have heard mixed things about adding baking soda.

Any suggestions as to what to do?

[Mrs Smith]

I would discourage you to do the baking soda thing, as it is a "quick fix," and will probably create more problems than it will solve in the long run. Are you dosing anything to try to manage the problem? (Like B-Ionic) What have you tried?

I'll admit that I'm not the expert, but more information about the situation may help others.

Danielle

[AquaticCo]

Are you running a CO2 reactor?

[Spanky]

Sort of the same question, are you blowing off enough CO2?

[Piero]

does that mean he should increase the C02 bubble count?

Also...how do you know if your reactor is c02 saturated? I've always got bubbles at the top of my reactor it seems, and wondering if I'm wasting c02 that's not going into solution in the reactor column. But my bubble count is only 2-3 bubbles/sec., and that's not fast at all.

[murphy]

I am not running a CO2 reactor.

I have been adding Kent CB part A & B. But my calcium (approx 360-380) and Mag (1,150 and climbing) have been low, so I have been adding some Turbo Cal and Mag to the tank to bring the levels up. Also, I been adding the Superbuffer dkH at night to try to correct the low ph. But, I feel like it is increasing my kh, which was 13 today. The ph is 8.14.

I am so confused as to what to do and I feel like I am adding way too much to the tank. But I really have no idea how to bring up the ph and lower my kh. I understand the mechanics, but at a loss for a solution.

[Spanky]

What I was thinking is that a CO2 build up, with or without a reactor, will drive your Ph down. Even with high alk. It's just more common with a reactor because if you're not careful, you can add too much CO2 to the system.
The cure is more surface agitation/circulation and sometimes a bigger skimmer.

[SteveNichols]

If you read this you may get the answer to your question.

[murphy]

Great article. That is actually one of the best I have seen.

Thanks.

I will it, hopefully my ph will adjust accordingly as I set by other parameters.

[tdwyatt]

Just curious, how are you measuring your pH, and what time of day and how often are you doing your measurement? If you're using a kit, which brand?

What is your salinity and how are you measuring it?

Are your corals doing well?

What kind of circulation do you have, and do you use a skimmer?

Do you have a lot of macroalgae, and/or a good coating of coralline algae?

Inquiring minds want to know!

[SteveNichols]

Why Tom, just because all of that affects pH?

[tdwyatt]

[murphy]

How are you measuring your pH?

Pinpoint Monitor. Range is 7.9 in Morning to 8.06 in Evening

What is your salinity and how are you measuring it?

Refactometer - 1.025

Are your corals doing well?

Yes

Feather Duster
Green Spotted Mushrooms
Green Hammer and Purple Hammer
Cabbage Leather
Clove Polyps
Xenia pulsing
Bubble tip anemone
Maroon footed anemone
2 Sebae anemones
2 Mangroves in refugium


What kind of circulation do you have, and do you use a skimmer?

Aqua C Remora protein skimmer w/ a Maxi Jet 1200
Rainbow Lifeguard Fluidized Bed Filter with pump
2 Maxi Jet 900 for circulation
20 gallon refugium w/ Mag 3 pump for return
UV Light
60lbs LR
2 1/2 to 3" sandbed with lots of critters
2 Coral Life Lights (10,000K and a Trichromatic 6,500K)

Do you have a lot of macroalgae, and/or a good coating of coralline algae?

Moderate

[Spanky]

Range is 7.9 in Morning to 8.06 in Evening

hmmmmm

If it was me, I wouldn't worry about it.

[tdwyatt]

Originally posted by Spanky
hmmmmm... ...If it was me, I wouldn't worry about it.

Me either Spanks, although I would be suspect of the subject tank pH readings at this point. I don't know if you follow a regular maintenance on the pH probe but here is a thread on the topic. The probes should be replaced every 18 months, as well as routinely maintained and recalibrated mimimally every 3 months in tanks with high calcium usage and heavy Coral and coralline growth.

My personal recommendation would be not to worry if the corals look good. Don't do anything drastic at this point, rather, reevaluate every few days so long as the corals look good. Treat the tank, not the numbers, and do the probe maintenance as per the above referenced thread. Wouldn't hurt to go with the battery power supply on the Pinpoint if you use the AC adapter, as stray voltage will skew the values of the meter. If you use a battery, try changing it every month, and replace the one you have in the meter now as well. Many folks find that just doing the maintenance makes a world of difference in the readings.

Hope this helps