Switched Alk and Ca Chemicals and Now pH is Tanking. What do I do?

[deputydog95]

I had been using Seachem Reef Fusion for a couple of years, until I finally figured out that it was spiking my K to riddiculous levels (800).

While I was using reef fusion, my pH was typically around 8.1 ish at an alk of 8 dkh.

I switched to Red Sea's Ca and alk about a week ago and have been a pretty drastic drop in pH, despite still maintaining an alk of 8 dkh.

This morning it dropped to 7.6 ish. I'm a little concerned about the pH being this low.

I'm currently dosing Ca and alk on a 24 hour schedule.

pH seems to peak around 4 or 5pm, and bottoms out around 2 or 3am.

Any idea why this might be happening?
Anything I can do to counter this?

[aaronpentz]

Get in the habit of not chasing numbers.
Ph isn't a big deal if your tank is doing well. It's only an indicator. Also. When was the last time the probe was calibrated and or replaced. They have a useable life span so this should be part of regular maint. You should also verify this with a different not expired / recently calibrated test kit.

Dont adjust without secondary verification.

As far as the swing that's perfectly normal. The ph will rise with lights on and fall with lights off.

This is why some people run the refugium lights on the opposite cycle of the tank lights to help normalize this.

You can also dose calcium during the day and alk during the night

Sent from my SM-G955U using Tapatalk

[deputydog95]

Originally Posted by aaronpentz

Get in the habit of not chasing numbers.
Ph isn't a big deal if your tank is doing well. It's only an indicator. Also. When was the last time the probe was calibrated and or replaced. They have a useable life span so this should be part of regular maint. You should also verify this with a different not expired / recently calibrated test kit.

Dont adjust without secondary verification.

As far as the swing that's perfectly normal. The ph will rise with lights on and fall with lights off.

This is why some people run the refugium lights on the opposite cycle of the tank lights to help normalize this.

You can also dose calcium during the day and alk during the night

Sent from my SM-G955U using Tapatalk

Once I saw the drastic pH shifts, I immediately calibrated the probe out of concern. Same results.

It's just weird that the pH is so much lower using different chemicals, despite the Alk being the same.

I do run my refugium on an opposite lighting schedule.

How would you schedule the dosing to maintain a more consistent pH?

[bertoni]

7.64 is low enough that I'd look at a solution. If the measurement is correct, the problem is carbon dioxide in the air. The older alkalinity supplement might have had a lot of borate in it, which might help a bit with the daily lows for pH. Dosing the supplement at night might help a bit, as might fresher air. 7.64 isn't low enough to be a disaster.

Is this the tank with the Regal skimmer? Is the skimmer producing a good bubble stream? If not, better aeration might help a bit.

[nematode]

On the graph above is may 14 the day you switched supplements. That is a pretty dramatic switch cycling between 8.0 and 8.2 to cycling between 7.8 and 8.0. Seems like buffering capacity of the tank changed. No water change or other mod to the system at that time.