I have used natural predators to keep redbug population below the damage threshold in my 50 gallon breeder which contains mostly acros. I used Interceptor to knock the population down quite a bit, but there's Interceptor resistance as the population bounced back stronger between treatments. After the second Interceptor treatment, I stocked the tank with several acro crabs(Tetralia species), and a green clown goby (Gobiodon atrangulatus). Acros inhabited with acro crabs had major reductions in red bug numbers after a week and within 2 months, none were visible on the acro. Unfortunately, Acro crabs prefer acroporas with thick branches that form dense clusters--they do not like stags or open branched species. Clown gobies can be good or bad for acros as some species will actually feed on the polyps. I chose Gobiodon atrangulatus because there are published accounts of them specializing on copepods. I use only one in my 50 because breeding pairs will remove the flesh from acros when making a spawning site. I have never observed this Gobiodon feeding on Acropora polyps, but have seen this particular species picking at the surface of the coral where redbugs were visible. Recently, I added a small Macropharyngodon meleagris (Leopard Wrasse) and within 3 weeks, rebugs are below detectable levels throughout the tank. Since then, I paced a frag of Acrpora granulatus in the tank and no redbugs have been noticed on this preferred redbug host. It has taken my tank over 11 months to go from total infestation to undetectable levels so do not expect results overnight. Interceptor is a good and reliable treatment for redbugs, but it does tend to reduce biodiversity in tanks. My technique which relies heavily on natural predators may or may not work in all reef aquaria and further work is needed in finding the right combination of natural predators.
As Always,
Jim Z.
