Low ph and I'm not sure why

glb · Apr 10, 2015

Ph only down to 7.8 last night without dosing. Alk down to 11.4kh. Yay!!

Randy Holmes-Farley · Apr 10, 2015

:thumb:

puffer420 · Apr 11, 2015

Was reading the post and noticed you were talking about alk so thought I'd ask I'm trying to raise my alk to like 10 or 11 got it up to 9 from 7 in a couple days dosing kalk from my ato and adding 90ml of a sodium bicarbonate solution after 3 days of doing this it dropped from 9 to just about 7. My ph fluctuated up and down from 7.9 to 8.3 and calcium between 450 and 480. Don't understand why my alk won't raise

Randy Holmes-Farley · Apr 11, 2015

The higher you try to keep the alk and the higher you try to keep the pH, the more daily consumption of calcium and alkalinity will take place in the tank, so it can be hard to raise it all that much without getting substantial precipitate.

glb · Apr 11, 2015

Ph holding at 8.0 during the day. I'll measure Alk tomorrow and see what's up. As a side note, I added a heater on Thursday to offset the temp swings after I took off the lid. The temp went from 77-79 or 80. Sadly, my clownfish came down with what looks like the ich and died overnight. Could my dosing have weakened the little guy? Or can temp change my numbers in ways I'm not aware of? I'm calibrating it to 78.

glb · Apr 13, 2015

Ph only going down to 7.8 at night and tops at 8.0 during the day. This is the most stable it's ever been. I think these will be the highest numbers I can do with kalk and keep my Alk in check.

Randy Holmes-Farley · Apr 13, 2015

Seems fine to me.

glb · Apr 15, 2015

Ph has dropped a little. 7.8 in am and 7.9 this afternoon. Alk is still reading 11.4kh on Hanna and 8.5kh with Salifert. Very weird. Right now my luxeon lights are running like this: Blues at 40% for 8 hrs and Whites at 15% for 3 hrs. I lowered them to fight the algae. Now that it's better, and because I raised the lights up off the tank, would running the whites a little longer or stronger help with the ph?

glb · Apr 18, 2015

Very interesting. Turns out my Hanna Checker was wrong. I changed the battery and replaced the expired reagent and it now reads 8.8kh, which corresponds to the Salifert readings. I can add more kalk to keep Alk and ph up. This seems to be a good reason to have more than one kind of test kit around.

glb · Apr 21, 2015

I was able to raise Alk since my tester was wrong. Now the Hanna and Salifert are reading about the same. I've been adding 1/3 cup kalk in the morning, after work and at bedtime. I'm going to measure Alk daily for a bit and see if this works. Today Alk was at 10kh, exactly where I want it. Ca stays around 490ppm and Mg at 1320ppm. I never have to dose mg. That might change as soon as I have more in the tank.

glb · Apr 21, 2015

Oh, and ph is staying between 7.8-8.1, more or less. GHA is going away and my crabs and snails are active. I think my little tank has finally turned around.

Randy Holmes-Farley · Apr 21, 2015

glb said:
Oh, and ph is staying between 7.8-8.1, more or less. GHA is going away and my crabs and snails are active. I think my little tank has finally turned around.

:thumb:

Happy Reefing.

glb · Apr 23, 2015

7.8-8.0 seems to be as high as I can go and keep kh around 10. Yesterday it was 10.5 so I didn't add kalk. This is certainly quite the balancing act! Another question. Do you have an article about how lighting affects ph? I know ph goes up during the day but I'm not exactly sure why. Is it the light itself or the metabolic activity in the tank as a result?

glb · Apr 24, 2015

I bought a little coralife skimmer so I can hook up the airline to it instead of having an airstone in the tank. I know they aren't super efficient skimmers but I thought the aeration would help with the ph. Does having a skimmer offer other options for the co2 problem?

zesty · Apr 24, 2015

Randy Holmes-Farley said:
Aeration can make low pH worse if you home air has elevated CO2 in it.

Aside from fresher air, options include limewater and a CO2 scrubber on a skimmer inlet or air stone.

glb said:
I bought a little coralife skimmer so I can hook up the airline to it instead of having an airstone in the tank. I know they aren't super efficient skimmers but I thought the aeration would help with the ph. Does having a skimmer offer other options for the co2 problem?

Like Randy mentioned before, if you are pulling in air with elevated c02, you will reduce your pH.
I don't think I would remove the skimmer, but just keep an eye on your levels once your add your skimmer and see what happens in the first few hours/days... Then adjust from there.

glb · Apr 24, 2015

Thanks. I will have to keep an eye on the ph. I also got the skimmer knowing I could add a co2 scrubber to the air line, so that is my next step. What is a good adsorbent? Lime? The color changing granules?

glb · Apr 25, 2015

Just installed the skimmer. We'll see if it actually skims. Lol.

glb · Apr 25, 2015

Also, I picked this up at the LFS. It's supposed to raise ph without raising Alk/ca. Could I use this at night or when I can't use kalk because the Alk is too high?

ImageUploadedByREEF2REEF1429992582.802171.jpg

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Randy Holmes-Farley · Apr 25, 2015

Sorry, no. It raises alkalinity exactly the same as limewater (kalkwasser) for the exact same pH rise as both add hydroxide ion.

But it adds no balancing amount of calcium that limewater adds.

It just goes to show how incredibly uninformed many companies are about their own products.

glb · Apr 25, 2015

Randy Holmes-Farley said:
Sorry, no. It raises alkalinity exactly the same as limewater (kalkwasser) for the exact same pH rise as both add hydroxide ion.

But it adds no balancing amount of calcium that limewater adds.

It just goes to show how incredibly uninformed many companies are about their own products.

Bummer. The calcium bump from the kalk, which I like, is what this takes away. If my calcium is at 490-495 though, should I use this instead until it comes down? I want to not have wasted my money. [emoji15]