#ed_op#DIV#ed_cl#go with the actual tank size (100 gallons) to calculate the filtration, if you calculate for the displacement of the LR and LS you runthe risk of not having adiquite water flow/skimming/filtration. Hope this helps#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl##ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#tigersax7#ed_op#/DIV#ed_cl#