My filter is a central vortex with four filtration unit around it, not really a good system because the central vortex isn't big enough. This filter works well because i added à static K1 in the vortex and fluid kaldness in the second but before that it was a pity.
http://www.koi-bito.com/forum/attach...achmentid=1451
So I understood now that I should put a big vortex unit in place of this filter and feed the central vortex and the BS by that water.
Some work for winter ...