If you do decide on something a little more permanent you could always build a DIY Kalk reactor. That first shot is the original iteration from 2010. The second picture is the improved ghettorific Kalk reactor today. You can see the patch from the first version. ABS to PVC transition glue works well on many hard plastics. This container was some kind of pasta storage thing I think and a glued on pipe fitting. The top of the container is glued onto the bottom in the second version and all access is through the pipe fitting. It has a small return pump from a nano aquarium inside. The tall pipe is where the fresh water goes in, it is tall to stop syphoning from happening. The angled pipe spills the kalk into the sump. That little DIY reactor has grown a lot of corals in the last six years. I have actually purchased a pro stirrer but haven't set it up yet. Curious to see how well it does against my cheap, probably a little better... I also went upscale to a calcium reactor.
