for sps, and perhaps lps, its not the amount of available calcium/Alk (remember they are linked) its how they absorb it. For sps ans Acros its flow. if you want them to get bigger balance decent(in my case not great), Alk with light an major flow. you need to break that outer water boundary to make the minerals more available to the corals.
That's interesting. I actually reduced flow around them thinking that strong flow would effect them in the same way as touching them... they'd close up.
its not IMO the availability if the mineral in the WC that factors growth. its getting the mineral INTO the coral.
for the cal and alk balances re read this. use the graph to ascertain your position in relationship to some parameters w some pretty darned wide margins.
http://www.advancedaquarist.com/2002/11/chemistry
I was reading this article earlier today. I'm in zone 3; "hard to correct and fairly common." I have been adding buffer to help maintain pH, and this can be a source of the problem. I've discontinued buffering.
this is why i dont think trying to balance your alk based on the cal may be wise. re read and re read the skepticism of the accuracy of any test kit in this article.
if you test three times in a row and your cal and alk are in the target range,(mine is low btw so im going to add balanced 2 part OR kalk), your fine and the corals will grow.
if they aren't its more likely the answer lies elsewhere. Ie light food flow. w sps id wager flow.
the biggest burst of growth I have had in stony corals was w several large water changes then for a 6 weeks no dosing, Acro style etc in the highest flow in the tank, high nutrients and recently upgraded lights.
I'm going to increase the flow by making it more direct.
yes it sank my cal and alk, but did not stop them from growing.
