Calcium ATPase involved in Ca(2+) homeostasis as a component of the contractile vacuole complex. ATP + Ca(2+)(in) + H2O = ADP + Ca(2+)(out) + H(+) + phosphate Contractile vacuole complex. Localizes to the contractile vacuole membrane in unstimulated cells (PubMed:9885293). Localizes to the cell membrane and the contractile vacuole membrane in cells stimulated by calcium (PubMed:9885293). Expressed constitutively at very low levels during vegetative growth and throughout development. By calcium. Loss-of-function mutant (antisense inhibition) displays impaired growth in high Ca(2+) medium but normal growth in low Ca(2+) medium. Antisense inhibition does not affect development in high Ca(2+) medium. Belongs to the cation transport ATPase (P-type) (TC 3.A.3) family. Type IIB subfamily.