Little lost on my ALK

[Eienna]

OK, so my params are as follows:
salinity 1.026
Mg 1300
Alk 5.9
Ca 340
I can't figure out why in the world my alk is so low. Should I be worried?

 

[fishroomlady]

I would say that's not good

 

[Eienna]

I don't understand it. I was under the impression that it should be controlled to an extent by cal and alk, and the corals look happy as ever, yet it's waaay out of whack.

I was using my Red Sea kit...I'm gonna try it with my API and see what that says.

 

[Eienna]

API kit says 8.

 

[Eienna]

pH 7.8 according to API.

I did a large topoff today to get to the proper salinity. Could that be the culprit?

 

[Randy Holmes-Farley Verified Community Expert]

5.9 is dKH, right?

Are you dosing anything?

It is normal for alk to drop if you do not actively maintain it.

 

[Randy Holmes-Farley Verified Community Expert]

I'd also look to boost the calcium.

What salt mix are you using?

 

[Eienna]

Yes, dKH.
I use the Red Sea Coral Pro salt, and have dosed some cal and mag in the last few weeks.
It just hit me that this is the first time I've tested ALK since I got this tank about a month ago, and approximately half the water was in the tank when I bought it secondhand. The guy dosed calcium but did not dose mg, and he'd had it for about four months. Maybe that's the reason, and it just hasn't had a chance to come back up???

 

[Eienna]

Both cal and mag were low when I first tested, though mag was the worst. I don't believe I checked alk at that time.

 

[Eienna]

Doesn't adding calcium bring the alk down?

 

[NanaReefer]

Not if equal amounts of ALK & CA are added.

 

[Eienna]

Hmmm
But my mag's in the right place, am I right? So adding calcium right now would bring it down?
Sorry, just trying to understand this.

 

[Eienna]

OK...so if I follow what I understand of Randy's advice and add the calcium, and it doesn't go where it's supposed to, would it be time to dose one of those alk booster products?

 

[jayhawk]

The first thing is to get an accurate baseline. Is the API test kit new or old? Having a good test kit will solve a lot of problems and prevent overdosing. Once you get a good test kit, test the tank water and the water used for changes. The water used for changes, if mixed right, should tell you if the test kit is reading accurate or not. Red Sea is consistent and if the mix says 7.7 Alk or 11 Alk is the result, it will be close. Test the tank water next. If the water is low on Alk, dose with a good supplement until you get what you want. Be cautious with raising it too quickly. Once at the levels you want, test the water every day or every other day. You are going to want to know how much your tank is consuming. Once you know your daily consumption, dose accordingly. I noticed you mentioned PH. I wouldn't get wrapped up in it right now. If you maintain Calcium (400 ppm), Magnesium (1300 ppm), Alkalinity (8 - 11) and Salinity (1.025), you are headed down the right path. Suitable PH is a result of maintaining the 4 mentioned parameters. As you progress you will get into the other aspects but master the basics first. Hope this helps

 

[Eienna]

The API's not expired, if that's what you mean.
OK, I will check some fresh mixed water.

I mentioned pH because I figured if that was off it might help determine what's wrong.

 

[watchguy123]

Depending on the size of your tank and the type and amount of coral inhabitants you keep, most likely you will require some level of supplementation of your Alk, ca and mag. Water changes on a nano might do as well with very few inhabitants. But most growing coral particularly sps, will require supplementation of these specifics either manually, doser or calcium reactor. Randy has written some wonderful articles on this topic, reef chemistry, and every reefer should understand this clearly. Otherwise how else's would you have a happy tank. Oh, and you have to test regularly. Although some get away with just being a keen observer, that seems to be a risky approach unless you have a consistent routine and have learned to maintain parameters with either your routine or equipment.

Oh and test kits, I hate them. They seem to be inconsistent, from manufacturer to manufacturer. But they are the best we have so far

 

[Eienna]

I don't dare touch anything today, since I already dropped the salinity. Tomorrow I will look and see if I have an alk supplement. I know i have cal and mag.

 

[Eienna]

OK, I tested a fresh batch. I have come to a few conclusions.
1. The Red Sea test is correct, therefore the API test STIIINKS
2. My tank has seriously low alk.

Guess I gotta fix that.
Any suggestions? I appear to have a partially-used B-Ionic alk supplement (part of a 3-part, I guess) in my box of supplies. Should I use that?

 

[Randy Holmes-Farley Verified Community Expert]

Doesn't adding calcium bring the alk down?

No. Adding calcium over time and allowing organisms to use both calcium and alkalinity to make skeletons "allows" the alkalinity to decline, but it does not drive alkalinity down unless you add way too much calcium.

 

[Randy Holmes-Farley Verified Community Expert]

OK, I tested a fresh batch. I have come to a few conclusions.
1. The Red Sea test is correct, therefore the API test STIIINKS
2. My tank has seriously low alk.

Guess I gotta fix that.
Any suggestions? I appear to have a partially-used B-Ionic alk supplement (part of a 3-part, I guess) in my box of supplies. Should I use that?

I'd use an amount of B-ionic to boost the alkalinity by 1 dKH per day for a couple of days and see where you stand.

Add both parts of the B-ionic equally (if you have the calcium part as well, if not, use just the alk part and we'll deal with calcium later.

This calculator shows how much to add:

Reef Chemistry Calculator