Filtered aquatic small tubular mesh-bottomed containers (FAST-MC): A low-cost, efficient method for rearing zebrafish larvae in filtered water

Care for larval zebrafish (<i>Danio rerio</i>) can be taxing and time-intensive, as embryos/larvae are housed in petri dishes or well plates which require daily care. Lack of filtration in the dishes can affect overall water quality, especially in ecotoxicological exposures which can last weeks. This report describes an alternative method, Filtered Aquatic Small Tubular Mesh-bottomed Containers (FAST-MC), which separates larvae into petri dish-sized housing containers maintained in a larger volume of filtered water, mimicking the larger, recirculating systems used for adults. To validate our method, we raised zebrafish larvae in FAST-MC containers for 4-weeks and compared overall survival, behavior, and water quality with larvae reared for 4-weeks in standard deep dish petri dishes. Overall, this method provides a low-cost alternative for housing larval zebrafish that is amenable to experimental manipulation and suitable for toxicological and/or pharmacological studies.•An easily constructed float can hold small mesh-bottomed (hatchery-type) containers in a larger aquarium allowing constant water filtration and improved water quality.•Each mesh bottom container can serve as a housing container for experimental exposures, similar to multiwell plates.•Zebrafish larvae raised in the mesh bottom containers had increased survival and activity compared to larvae raised in standard petri dishes.