Alk question

[rick4him]

I have a question concerning alk. I have a 34 gallon tank that I've had for about 1 1/2 year. I often check Calcium, Ma, PH, etc....I have not often checked Kh. I'm not sure why, I just never did. Everything in my tank has been doing well (as far as I'm concerned.) A few weeks ago I decided to randomly check the Alk. I have 2 test, that test for KH. You put drops in until the regent turns from blue to yellow. It normally takes about 12-13 drops to get the recent to turn blue. The instructions say to take the number of drops and multiple by ten then divide by .056 to get the dkh. When I do this my dkh is around 6.72-7.28. I notice that if I loose about "1 drop" a day. So if it is 12 today, and I do nothing, it will be 11 tomorrow. I usually do a water change every 7-10 days. When I tested the alk last time I was around 3.36. So this means that I've been loosing that much between water changes. I'm not sure if this usage has increased as of late since some of my lps/sps have grown to some pretty good sizes.

I want to be sure I'm doing the math correctly, because when I test my fresh salt water it is also at about 12-13 drops. If that is correct, and I'm supposed to be 10dkh, then that seems way off. Meaning that I have never had enough alk in my tank ever. (Since I"ve been using the same salt mix.) I'm using IO, by the way. I've seen other people who use IO say there alk is higher, so I'm not sure if they are referring to dkh when they say that, or something else. I've used several test kits, and it is always that with my new water.

I've been using the reef calculator to add about 1/2 -1 teaspoon per day to get my dkh up. However, I'm thinking I need to add more, since adding 1 teaspoon raises the dkh up about 1, and that is about how much I'm using. So my dkh isn't really raising, rather staying the same.

I'm just curious what I should do. My ca is around 410 or so, and my ma is on track. My salinity is .025. I have some super buffer and I have some Kalk that I bought. I'm curious if I should put some of one of these to my top off water. I use a Tunze ato. I have read that some people use this, but I read on the kent website that you are supposed to use some sort of special drip device if you use Kalk.

This is my first time to look into this, and want to know if it is normal to have to add 1-2 teaspoons of baking soda every day into my tank. That seems like a lot. Please let me know if my math is right, and what I need to do..?

Thanks

[Randy Holmes-Farley]

Anywhere in 7-11 dKH is fine, IMO. If you want to keep doing it via water changes, that is ok, but as demand rises, that will soon fail to be adequate.

Yes, it is normal to have to add alkalinity somehow every day, especially if you have good coralline algae or hard coral growth. Baking soda is fine, but a two part or limewater might be even better and easier way to maintain both calcium and alkalinity.

This has more:

The “How To” Guide to Reef Aquarium Chemistry for Beginners, Part 2: What Chemicals Must be Supplemented
http://reefkeeping.com/issues/2007-04/rhf/index.php

[rick4him]

Anywhere in 7-11 dKH is fine, IMO. If you want to keep doing it via water changes, that is ok, but as demand rises, that will soon fail to be adequate.

Yes, it is normal to have to add alkalinity somehow every day, especially if you have good coralline algae or hard coral growth. Baking soda is fine, but a two part or limewater might be even better and easier way to maintain both calcium and alkalinity.

This has more:

The “How To” Guide to Reef Aquarium Chemistry for Beginners, Part 2: What Chemicals Must be Supplemented
http://reefkeeping.com/issues/2007-04/rhf/ind
Hey ex.php

Hey thanks! There is a lot on that page....but really great info.

I have a 5 gallon jug, would it be ok to mix in some of this kalk that I bought? Or is super buffer better? From what I have read the super buffer isn't the same as kalk, in that it won't rise my alk...any truth?

[rick4him]

Also..is it normal for my fresh saltwater to be so low?? Do I need to be adding baking soda to my new saltwater in order to get it up to 8-10 dkh? Is that normal to have to do that?

[bertoni]

A teaspoon a day of baking soda for that size tank is very reasonable. Salt products seem to be a bit variable, and cover a fairly wide range of alkalinity levels. If you're worried, you could get an opinion with a different brand of kit, but I don't think I'd bother yet.

Kalk adds both calcium and alkalinity, in the ratio used by corals, but it can be dosed only as a fairly dilute solution, and should be dripped slowly, as topoff, because a large dose can spike the tank's pH. Using SuperBuffer or baking soda as topoff will work, too. If you don't mind doing the experiments to determine the right concentration, that'll be fine. I just dosed two-part by hand.