Where is my pH going?

ksarauer · 05-16-2005, 05:05 PM

I have never had a problem with my pH dropping below 8 until recently. It lowest drop is 7.9. I have turned off the CR, but am not sure if something else is causing it to drop?

Any ideas?

David Grigor · 05-16-2005, 05:35 PM

This is not unusual when running a CA reactor.

You shouldn't see any real negative effects.

You can use Kalk with your topoff to combat the lower levels because of the additional CO2 the reactor is adding to the system.......

ksarauer · 05-16-2005, 07:43 PM

I have been removing a couple gallons every couple days to keep the ph up. I have not ran the CA reactor for a couple weeks.

How long will it take for the pH to come back up to reasonable levels.

Here are my water params as of Saturday
Temp 82.7
pH 7.98
ORP 357
dKH 12.5
alk 4.46
Mg 1200
Ca 405
NO2 0

David Grigor · 05-16-2005, 10:53 PM

IMO: They are resonable levels as is. A low of 7.9 is not a concern. Especially if your not seeing any issues with the livestock.....

Getting the Magnesium levels up to 1320-1350 may help keep it buffered as well.....

ksarauer · 05-18-2005, 12:02 AM

Thanks for easing the worries Dave, I've been waiting for things to start dropping. When I got home tonight, my pH was 7.79. I brought it up to just below 8 this morning.

What is a good additive for bringing the Mag up?

Also what are the side affects of putting in a buffer for the pH? Good idea / Bad idea? I've slowly dripping in kalkwaser in the morning and evening to bring it up to 8.

Any ideas what would cause this? It has happened in the last week, and the only change was the new lights?

Kevin

Sea monkey · 05-18-2005, 12:57 AM

Quote:

Originally Posted by David Grigor

This is not unusual when running a CA reactor.

i would venture to say not only is it not unusual but normal.

K Sarauer · 05-18-2005, 08:20 AM

pH is at 7.45 this morning.

I did not bring it up to 8, but I added (slowly) about 8 oz of some milky kalkwaser last night. Is it OK if I add more kalkwaser than this at a time? I been putting in ~8oz in the am and ~8oz in the pm. The pH is ahead of me and I need to put it back in check!

Any comments / ideas would be appreaciated...

Thanks, kevin

K Sarauer · 05-18-2005, 08:22 AM

Could it be my salt? I'm using Red Sea salt?

Twins Guy · 05-18-2005, 08:52 AM

hey kevin-have you measured it in the am recently or just the pm? ph in a tank setting can easily fluctuate .3 units from a low in the am (before thte lights go on-because critters are respiring-producing CO2(an acid)) to a high around the time the lights go out (cuz critters are phosythesizing all day-consuming CO2). i think its possible that your 7.79 the other day started out similarly low. now that doesn't address the lows you've been experiencing-maybe its eases your concerns about this morning though.

so you changed the lights recently? how are your corals looking? it was a significant jump in intensity right? i can imagine that stressed corals (aka all of a sudden-lots more light) would not photosynthesize as actively which could depress the ph a bit.

have you done any water changes recently-or lost any animals? just thinking about the build up of organics and how that can drop your ph? my first reaction to any problem in a tank is usually a w/c.

imo-overreacting to lows (whether its ph, sg, alk, Ca, dosing too much kalk, buffer, whatever) can be worse than slowly correcting the situation. drastic and dramatic changes in water chemistry seem to be more detrimental than the low parameter itself.

my advice for now-be careful "correcting" your ph-go slow!
tg

Twins Guy · 05-18-2005, 09:00 AM

and i don't have any experience with kalk on that size system-wish i could be more help. to illustrate my point about going slow-baby steps-most commercial buffers recommend bumping ph up only like .1/day cuz you don't want to piss off your critters. i'm sure your kalk additions are doing that and then some so...
tg
now lets find the source of this rather than just correcting a symptom

otolith · 05-18-2005, 10:14 AM

Kevin, what's with the 2 logins?

I agree with TG, that it's prolly been like this for a while, and it's nothing new. A simple thing you could do if you live in a well-sealed house that doesn't have an air exchanger is pump on fresh air through your system by hooking up the air input for your skimmer to an outside line.

Sea monkey · 05-18-2005, 10:40 AM

Quote:

Originally Posted by K Sarauer

pH is at 7.45 this morning.

I did not bring it up to 8, but I added (slowly) about 8 oz of some milky kalkwaser last night. Is it OK if I add more kalkwaser than this at a time? I been putting in ~8oz in the am and ~8oz in the pm. The pH is ahead of me and I need to put it back in check!

Any comments / ideas would be appreaciated...

Thanks, kevin

ok now that is low : (

ReefSitter · 05-18-2005, 11:01 AM

7.45?? and you are not running your CA reactor at this time? Seems real low even if the CA reactor was running. You said you never had a problem until recently, and after turning off the CA reactor, the ph continues to drop???

Are you sure your ph monitor is calibrated correctly or is something going wrong with the ph monitor? Might not be a bad idea to check the monitor before adding any buffer.

David Grigor · 05-18-2005, 11:16 AM

You really don't want to be manually adding Kalk. Best to incorporate it into a autotopoff ( with failsafes in place so you don't add too much too fast ) where it just adds a little a time periodically throughout the day.

To add to what Mark mentions, what are you using to measure ph. I have a pinpoint meter that using a 9v battery. When the battery is low the readings get off ( reporting lower than actual ). Also, best to recalibrate to make sure your really seeing a true PH drop.

Twins Guy · 05-18-2005, 02:32 PM

diggity also makes a good point about the sealed up house thing. its been chilly and wet recently and if your house is "airtight" like many newer houses they can accumulate alot of CO2 which will keep your ph down. good point ole chap! even an airline out the window from the venturi or becket on your protein skimmer can do wonders...right greg? if i were a betting man...

and checking the calibration on the ph monitor would also be a great idea.

tG