Should I be dosing?

[richardhmc]

Hi, I have a 50 gallon tank with a 20 gallon sump. It is a reef tank.
I use Instant Ocean salt and my calcium level is at 420 ppm and my alkalinity is at 10 dkh. This is usually constant because I do a 40% water change every week so the water is constantly replaced.

People say that I should be dosing calcium, alkalinity and whatnot. However, judging by my levels, should I still dose? Thanks!

[sirreal63]

Doesn't sound to me like you need to supplement, you are doing that with water changes. If the parameters in the tank are 420 and 10 and stay consistent, there is no need to dose.

[richardhmc]

Alright thanks!

but my alkalinity at the moment is 8 dkh. It tends to drop very quickly even though I do frequent water changes. Calcium is about 400 ppm.
Having the calcium and alkalinity is bad correct? It should be steady at a specific concentration?

[reef_doug]

Consistency is the key. You may want to look into maintenance with kalkwasser or two part.
Your last reply does indicate your tank has a demand not met by water changes alone, although 8dKH and 400 Ca are great, consistency would be the goal.

[Felixc395]

Consistency is the key. You may want to look into maintenance with kalkwasser or two part.
Your last reply does indicate your tank has a demand not met by water changes alone, although 8dKH and 400 Ca are great, consistency would be the goal.

I couldn't agree more.

Alright thanks!

but my alkalinity at the moment is 8 dkh. It tends to drop very quickly even though I do frequent water changes. Calcium is about 400 ppm.
Having the calcium and alkalinity is bad correct? It should be steady at a specific concentration?

Yep, like suggested you should have it as stable as possible. If you want less of a hassle, then two part would probably be easier. Kalk can be complicated, but still isn't to tough to handle.

[sirreal63]

Agreed completely with above.

[richardhmc]

Thank you all for your input. Is it true that kalkwasser will dissolve phosphates?
Which is better to use, two part or kalk? Thanks.

[reef_doug]

Kalkwasser does help to percipitate phosphate out of the water column, but I believe the jury is out if it settles in the rock & sand or not. In some tanks, kalk alone can't keep up with the alk & Ca demand. FWIW... Randy has mentioned he uses Kalk.

Two part is easier if you need independent control of Alk & Ca.

[bertoni]

Kalk might help remove phosphate from the water column, but that's never been proven to be true.

Many tanks drop 2-3 dKH per day, which is why supplementing calcium and alkalinity daily is very common. A two-part like B-Ionic is an easy way to get started, and there's a DIY recipe to save some money. Kalk is very good, too, and might work for you. It's more complicated to dose than a 2-part, though, because it should be dripped in some way. This article has more details:

http://reefkeeping.com/issues/2005-01/rhf/index.htm

This article might help, too:

http://reefkeeping.com/issues/2007-04/rhf/index.php