A fluid compensation apparatus is configured to provide replacement fluid to a fluid-based cooling loop, while removing dissolved gas or gas in gross bubbles from the cooling loop. Removal or reduction of gas from the cooling loop reduces or prevents pump vapor lock. The removed gas is retained within the fluid compensation apparatus. The fluid compensation apparatus is configured to prevent the trapped gas from being re-introduced to the fluid-based cooling loop, regardless of the orientation of the fluid compensation apparatus. Additionally, the fluid compensation apparatus is configured to remove gas from and add fluid to the cooling loop with limited or no pressure drop between the inlet port and the outlet port of the fluid compensation apparatus. As a result, the pump does not require additional power to compensate for such a pressure differential.