If you’re into fish or invertebrate breeding, or even if you just have them spawning in your reef tank, one of the largest hurdles is getting the offspring out of your aquarium and into a larval rearing environment. You may have heard about a “larval snagger” on more than one occasion, and more often than not, then name “Vossen” comes up in the same sentence
It’s been a few years since Chad Vossen first designed and built his larval snagger. It’s an air-driven light trap designed to be placed in the aquarium on “hatch night”. With all the circulation in the aquarium turned off, and all the lights off, a pinpoint light source is used to attract positively phototrophic / phototaxic (attracted to light) organisms to the trap’s intake. These organisms, most often larval shrimp and fish, are swept into a large collecting chamber where they are held until the aquarist can come back later and remove them from the trap to place them in a culture vessel.
This is not our first look at a Vossen Aquatics Larval snagger; I first tried one years ago. However, I wanted to see how Vossen had refined his design and how he was now packing and shipping these traps. Here’s a look at the current incarnation of the Vossen Aquatics Larval Snagger (update – I should note that the reason I needed a new one is I loaned mine out and well…people really like them).
The trap goes on the inside, the light source on the outside glass positioned at the trap’s intake. The only other requirement is an air-pump, air tubing and needle valve (all attached to air tube at upper left) which allows you to drive and control the flow through the trap. Water enters the intake, and exits through the large diameter screen in the main holding area. Too little flow (not enough air flow) and you won’t trap much. Too much flow (too much air) and you’ll pin all your larvae to the exit screen despite its large diameter.
You need only search around a little bit to find out just how popular and well-received the Vossen Aquatics Larval Snagger has become. We’ve been told that these traps have quite literally been shipped around the globe!
It obviously will not capture everything, but this larval snagger will give you a chance to collect larvae that might otherwise be lost to the filtration or tank inhabitants. Have you tried Vossen’s Snagger? Let us know what you think in the comments below!