We make steps in a new direction by considering fluids with EoS of more general formF(ρ,P)=0. It is thought that there should be interaction between cosmic fluids, but this assumption for this stage carries only phenomenological character opening a room for different kinds of manipulations. In this paper we will consider a modification of an interactionQ, where we accept that interaction parameterb1(order of unity) inQ=3Hb1ρis time dependent and presented as a linear function of Hubble

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... Hof the formb0+btH, wherebandb0are constants. We consider two different models including modified Chaplygin gas and polytropic gas which have bulk viscosity. Then, we investigate problem numerically and analyze behavior of different cosmological parameters concerning fluids and behavior of the universe.