Qalfoofka saddex-daanka ah ee saliidda ah, oo sidoo kale loo yaqaan furaha shaandhada saliidda saddex-daanka ah, waa aalad si gaar ah loogu talagalay beddelka filtarrada saliidda ee matoorada baabuurta. Waxay caadi ahaan ka kooban tahay saddex daan oo la hagaajin karo si loo adkeeyo loogana saaro filtarrada cabbirrada kala duwan leh. Qalabkan waxaa sida caadiga ah loo adeegsadaa marka la beddelayo saliidda si loo fududeeyo saarista iyo rakibidda filtarrada saliidda.
Tilmaamaha furaha qaybta saliidda ee saddexda daan waa sida soo socota:
Markaad isticmaalayso furaha qaybta saliidda ee saddexda daan, hubi in daanka si sax ah loogu hagaajiyay cabbirka si ay ugu habboonaato shaandhada, si ammaan ah ugu dhejisan oo codso xaddiga saxda ah si aad uga saarto ama u rakibto shaandhada. Qalabkani wuxuu kaa caawin karaa inuu fududeeyo dayactirka isbeddelka saliidda, isagoo hubinaya in injiinkaagu si habboon u socdo oo uu ilaaliyo waxqabadka ugu fiican.