Whats a good Alk Level?

[Monster_13]

My tank is at about 5.5mg/l is that pretty good? Thanks!

[RussC]

I am a rookie at this but asked the same quesiton. Its been some time ago but I seem to remember my LFS saying between 8-11 for Alk. Double check that, though.

[Monster_13]

Woo that sounds really high

[bdr127]

Note the unit you are referring to..... Monster_13 is using meq/L, and RussC is most likely using dKH....

Randy Holmes-Farley (Reef Chemistry Forum Mod, and brilliant chemist :)) recommends 2.5 - 4 meq/L (7-11 dKH).

[Monster_13]

Okay good, but, if it is too high, how do i get it down?

[bdr127]

Just wait until things in your tank use it up.... stony corals, snails, coralline algae.... It'll come down. If you really really want it to come down immediately, then just do a water change. :)

[Monster_13]

Thanks:D

[Newreeflady]

I like 11-13dkh

[kozmo02]

also, if you are adding a superbuffer to your RO water cut back on that for a while and that will help lower it.

[RussC]

What benefits do folks see to the different levels of Alk discussed above? Any difference in the tank inhabitants based on the different levels?

[kbd]

Excuse me, but Monster_13 said his alk was 5.5 mg/l, not 5.5 meq/l.

5.5 mg is 0.09 mMoles HCO3, being 0.045 mMoles CaO, ie 2.52 g CaO per litre.

That is 0.252 dKH. Basically zero.

If he meant 5.5 meq/l, that's 2.75 mMoles equivalent of CaO, so 154 g CaO per litre so 15.4 dKH.

Just in case ! The remedy will partly depend on the Ca situation.

Hth,

kim

[bdr127]

Originally posted by kbd
Excuse me, but Monster_13 said his alk was 5.5 mg/l, not 5.5 meq/l.

That is 0.252 dKH. Basically zero.


That's why I presumed the original post to be a typo... ;)
:D

[bdr127]

IME, however, I like to keep my alk at least 12 dKH in my SPS tank.... I feel like being a little high is better than a little low for those guys. {shrug}

[Monster_13]

I think im going to invest in a new test kit so we don't need to deal with weird units and confusion Lol:lol:

[sjvl51]

I found this article the best for explaing Ca and Alk and how to adjust each

http://www.advancedaquarist.com/issues/nov2002/chem.htm

Vickie