Well, it is a realatively new site... one I am sure will gain some polish to it when Scott has the time (you know...
after he finishes our skimmer
).
As for WCs.. I am not a big proponent of them.. here are the reasons that read for why we should do them.. whether it be 10%, 20%, etc :
1. Replenishes trace minerals and so forth
While I agree with this to a certain degree, I feel that firstly, only changing 20% out would have a minimal affect on the overal level of the trace elements. And it would seem easier to just replace the missing elements (but not as profitable for the salt companies). Some of it gets put back through the calcium reactor anyways.
2. Nutrient export
There are other ways to achieve this. Large skimmers, maintained refugiums with macro algae (regularly harvested), Large skimmers, additives that make certain nutrients more skimmable, Large skimmers (ok, so I listed large skimmers a couple of times... can you tell that I feel that they are an integral part of a good reef system ?
), GAC, RowaPhos, etc. While a WC is a great, quick, way to export nutrients, again it only impacts 20% of the built up nutrients.. so if the nitrates are at 40 ppm, a 20% WC would bring them down to 32 ppm.. not really a great leap forward there. Using a something like a DSB/RDSB, or other nitrate consuming bacteria (there is some nitrate reduction product that comtains this bacteria in a bottle, that has been reported to be quite successful). The same thing goes for phosphates.
3. Heavy metal build up export
This one is great... exporting something other than nutrients, that has built up in our systems.. since they are closed systems, I still have not heard where these metals come from and how they build up/increase to where they need to be manually exported.. I would just say stop adding whatever is adding the heavy metals.
Those are the 3 main bullet points I have seen for advocating WCs... and my responses to each one.. so come on.. flame me for my beliefs
P.S. I would still like to have a WC sump setup... I just like the concept. And if it were easier to do a WC I would probably do them more often.. even though I do stand by my comments above.