kalk reactor
 

I am thinking about giving one of these a try since I have been having no luck with sps in my 75G tank.... any opinions on these units?

what are your levels in ur sps tank. if something else is off kalk wont help.

though the diy kalk stirrer kit from avast looks pretty good. AT $150 its tough to beat and if it ever breaks you know how to fix it, LOL

Or simply set up a drip or add some kalk to your ATO. Much cheaper and nothing to break down.