Dosing is the "poor man's" method of adding
Ca (And sometimes other elements) to your water. I say poor man's, but its not really rocket science. Its simply a method of using a container to mix in, tubing with a switch on it (Controls the drip rate) and gravity feeding it into your sump/tank. Not exactly your question, but this should give you and idea of dripping method..
http://www.oc-creative.com/reef/forum/forum_posts.asp?TID=1512&get=last
By comparison, this is a link to one persons
diy ca reactor..
http://www.hawkfish.org/snailman/diycareactor.htm Not quite the trivial task as a doser. If $$ is no issue, lots of folks would have you go with a reactor since its a bit more automated and doesn't require frequent mixing. In my case, I mix about 2.5G of water with about 4 tsp of
kalk twice a week. Some weeks only once, depending on the tests. Reactors bring with them, typically, a little
PH drop and excess
CO2 issue. That is, most folks have to work through these issues. (I do not own a reactor, but more than likely a result of 'aggressive' use of the reactor). I'm sure someone will chime in with one and cover more on the reactor side. Again, dosing and reactors both strive to maint a good
ca/
alk level and in both cases you MUST stay on top of your
mg levels and monitor
ph. Other than that, it may boil down to a matter of $$..
Nother good converstation about reactors..
http://www.reefs.org/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=29&t=000008
Either way, your corals will love you for it!
GL!