Save Redfish from Amyloodinium

Save Redfish from Amyloodinium

In the 1980s I worked with another university's research team on redfish aquaculture as an advisor. This was while I was Aquarium Supervisor at the J L Scott Aquarium in Biloxi. I received a call from them to check out sick redfish in their indoor tank systems of 1000-gallon tanks with bead filters.

I could not examine the fish, so I told the staff to put the outflow of the bead filter into the tank at the edge and direct the water flow along edge so the water in the tank had a circular motion for a few minutes. Then we turned the filter off to let the water settle for a few minutes. I then had them put a siphon hose in the middle of the tank and siphon off water from the tank bottom into a bucket. I then stirred the water in the bucket in a circular motion and let it settle for a few minutes. Finally I used a pipette to draw off water from the bottom center of the bucket and looked at the debris with a dissecting stereomicroscope. After seeing what appeared to be small cysts I put the debris under a compound microscope and confirmed the cysts were from Amyloodinium ocellatum, a parasitic dinoflagellate found on the gills, fins, and skin of various saltwater fishes.

I explained to the staff what they had and that unless they followed my advice they would lose their brood stock redfish. I told them to get some large swimming pool diatom filters and put on the tanks to suck all the infective stages of the dinoflagellates out of the tanks before they could attach to the fish. Those stages remaining on the fish would mature, fall off, and then would either be sucked up as cysts or, after divisions, as infective dinospores. Then the fish would be free of Amyloodinium. Thereafter, they could leave the diatom filters on the tanks or use them periodically to keep the Amyloodinium under control.

They had no further problems with Amyloodinium. In the early 1980s I told various aquaculture ventures and public aquariums how to save their fish from Amyloodinium using diatom filters. I had already told fellow staff members the procedure to use on saving cobia, pompano, speckled trout, red snapper, striped bass, etc. from Amyloodinium at my organization.

To this day this is the easiest way to keep saltwater fish without worry from Amyloodinium.

Adrian R. Lawler, Ph.D. (C) 2012 --

　

Lawler, A. R. 2007. Diatom filters.
http://www.aquarticles.com/articles/management/Lawler_Diatomfilters.html