ph dropping

[jbed]

Randy,

Wish I didn't have to bug you on vacation, but this is starting to worry me.:(

I have gone back and read most of your articles, yet am still a little confused..

I am trying to correct a previous problem....overdosed seachem marine buffer...drove the alk to over 15...

Finally got my salifert tests in (ca & alk)...alk @ 4.8 and ca @ 230 ppm.

ph has never been a problem staying right at 8.18 - 8.21...

So I have been dosing Turbo Calcium for the past 7 days...and have brought the ca up to 380....consequently alk has dropped to 12.8 dkh ( as expected), but my ph is dropping more than I want.

When I started dosing turbo calcium on 6-26 my ph was 8.21. It has slowly dropped to 7.99 today, even though my alk is still high.

According to your "solving alk and ca problems", I shouldn't use more buffer, but adjust the ph by itself.

Should the ph drop even though the alk is still on the high side?

I am ready to start using the homemade ca and alk additive when I get the ph, alk, and ca where I want them....

Thanks for everything you do on this forum, and sorry again to bother you on vacation!

Tank: 135 RR with 30 gallon fuge and 20 gallon sump.

ph 7.99 (Hanna Phep 5) calibrated again today (2 point cal)
temp 79.7 (Hanna Phep 5)
Amm 0 (fastest)
Nitrite 0 (fastest)
Nitatrate 0 (fastest)
alk 12.2 dkh (salifert)
ca 380 ppm (salifert)

Using d.i. water tested at 3 ppm tds (hanna meter)

Using I.O. salt, but my first batch with Oceanic is mixing right now.

Thanks again Randy!:rollface:

[Randy Holmes-Farley]

When you are adding only calcium to make a correction, the pH often can drop because you are removing carbonate as corals calcify. That's the opposite of why pH rises when you add carbonate (like B-ionic). Removing it causes a pH drop.

You have a couple of choices. You can ignore the low pH during the correction, or if you are planning to use a high pH calcium and alkalinity system going forward (like limewater or a high pH two part system), then you can begin that now in addition to the calcium chloride.