In a system for liquid cooling of electronics, where the electronics are subject to rotation in space, a liquid coolant storage tank includes a degassing and vortex-preventing structure to allow bubbles to float to the surface of the liquid inside the tank, and also to prevent vortices from forming near the outlet from the tank. The structure includes nested tubes or conduits. An inner conduit extends from the inlet into the tank, and its open end is covered by a second conduit with a baffle across its end, so that the flow is directed by the baffle to flow back along the outside of the inner conduit, and inside of the outer conduit. Especially at the inlet, a third conduit with large perforations surrounds the open end of the outer conduit. Smaller perforations on the inner conduit at the outlet side discourage any vortex from forming there. Reversal of the liquid flow, and the gradual increase in flow cross section prevent surging inside the tank.