Liquid flow and control in a biological test array

A test array adapted for antibiotic susceptibility testing of microorganisms comprising:

• an elongate shaped body with opposed and parallel top and bottom surfaces separated by a generally flat sidewall and an opposed generally indented sidewall, said body having a length and a plurality of upwardly projecting microwells formed in the lower surface as a linear row of single microwells parallel to said length;
• an open solution receiving reservoir formed in the top surface of the test array;
• a sacrificial evaporation well formed in the bottom surface of the test array upwardly projecting from an open portion of the bottom surface and disposed between the row of microwells and the reservoir;
• an open first microchannel formed in the bottom surface of the elongate body and connecting each microwell to the sacrificial evaporation well;
• and
• an open second microchannel formed in the bottom surface of the elongate body and connecting the sacrificial evaporation well to the solution receiving reservoir.