A shallow, stable water dish is one of the most fundamental accessories in any cave gecko enclosure. Goniurosaurus species drink regularly from standing water sources, lapping from the surface in the same manner as other eyelid geckos. The dish should be heavy enough or weighted sufficiently that the gecko cannot tip it during nocturnal exploration, and shallow enough that the animal can comfortably reach the water surface without risk of submerging its head. Glazed ceramic dishes, natural stone bowls, and commercially molded reptile water dishes all serve this purpose effectively.
Dish placement matters more than many keepers consider. Positioning the water dish on the cooler side of the enclosure reduces evaporation rate and keeps the water temperature comfortable for drinking. Placing it near a frequently used hide encourages the gecko to drink during its active period without making a long, exposed crossing of the enclosure floor. In multi-hide setups, offering a second small water source near an alternate hide ensures the gecko always has access to hydration regardless of which refuge it selects for a given evening.
Water quality requires the same attention given to any captive reptile. Dechlorinated or filtered water should be used for both the water dish and for misting. Chlorine and chloramine in municipal tap water can irritate a gecko's skin and mucous membranes over time, and the chemical residues accumulate on surfaces in the humid enclosure environment. A simple water conditioner formulated for reptiles neutralizes these compounds instantly and costs very little relative to the health benefit it provides.
Drip walls and drip systems, while more commonly associated with arboreal geckos and chameleons, can serve as a supplemental hydration accessory in cave gecko enclosures. A slow drip running down a section of stone or cork bark creates a moving water source that some Goniurosaurus individuals prefer to a static dish. The drip also contributes to localized humidity and adds visual and auditory interest to the habitat. These systems require regular cleaning to prevent biofilm buildup in the tubing and reservoir.