View Full Version : Alkalinity at 12.5 dKH

02/13/2006, 12:55 AM
My tank measure Alk at 12.5 dKH (4.46 mg/l). Salifert says that natural sea water is around 8 so should I be worried or be doing anything? I know low alk is bad but 12 should be fine?

02/13/2006, 01:54 AM
12.5 isn't too bad unless your calcium is way high as well which may create a spontaneous calcium precipitation storm in the water column if one goes much higher than it already is but this is rare. Your calcium is probably a bit low right now since your alk is high which is normally the case.

02/13/2006, 03:13 AM
That's true actually. Calcium is at around 320 but I'm dosing with the Calcium part of B-Ionic (100cc every 2 days) and topping off through a Tunze calc dispenser with calcium hydroxide. My system is new and has no calcium needing livestock apart from one deresa clam and a small SPS acro so I'm hoping my buffering will get the levels up there and the tunze calcium dispenser can keep up with the calcium needs under I need a reactor.

So when calcium level rises, alk can go down?

Randy Holmes-Farley
02/13/2006, 06:29 AM
I usually recommend 7-11 dKH. It should fall on its own to 11 dKH or less in a day or two (once calcium is up to normal). No need to do anything else for the alkalinity. :)

I would add a lot of the calcium part of the two part system, or just calcium chloride, to boost the calcium to 420 ppm in 1 or two days.

This calculator shows how much to use, and the article guides you through the process:

Reef chemicals calculator

Solving Calcium and Alkalinity Problems

02/13/2006, 06:41 AM
That calculator is a great tool. It says that at 450 gallons with current Ca at 320 and desired level at 420 I need to add 2812 ml. Problem is that the B-Ionic bottle says recommend dosage is 1ml per 4 gallons and even less if using Kalk. Therefore I've been dosing 100ml per day last few days. Would you say it's safe to dose more?

Randy Holmes-Farley
02/13/2006, 07:47 AM
Forget the bottle dose. That is for maintaining levels. When you need a significant rise, you need to add a lot more than the "recommended" dose. That is not a problem. :)

02/13/2006, 08:08 AM
Great, I'll add 100ml every 8 hours or so. So will be set in a week....

Thanks for the help, Randy. :)

steve the plumb
02/13/2006, 11:14 AM
You can start dosing randys formula its much cheaper than buying bottles of products.

Randy Holmes-Farley
02/13/2006, 01:56 PM
You're welcome.

Good luck. :)

02/13/2006, 03:48 PM
<a href=showthread.php?s=&postid=6730934#post6730934 target=_blank>Originally posted</a> by steve the plumb
You can start dosing randys formula its much cheaper than buying bottles of products.
What is this formula?

steve the plumb
02/13/2006, 05:58 PM
Look and find Randys alk and calcium formula.I don't have the link but most people on this forum know it.You can ask randy.

02/13/2006, 08:32 PM
Randy? :D

Randy Holmes-Farley
02/14/2006, 06:14 AM
An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System

02/14/2006, 06:38 AM
Yikes, that's hardcore. :D

Maybe I'll stick to B-Ionic and Kalk for a while. :p

Randy Holmes-Farley
02/14/2006, 07:03 AM
B-ionic is a fine way to go. :)