A REPORT ON THE FIRST MIXED TANK
An initial report on metabataeus and our first mixed tank was a part of the Christmas 2004 issue of the FBnews email newsletter and is posted at www.fukubonsai.com/M-L2b3.html under the title: METABATAEUS! This continues that report.
Our first mixed tank was created in January 2004 using a 2.5-gallon
bowfront aquarium fitted with an airline and undergravel filter.
An extensive aquascape "cliff" is built up on the baseplate
and the uplift air column is attached to the baseplate in the back left
and is hidden by the aquascape.
Behind the cliff-face and the back of the tank, pre-inoculated high-velocity pumice ejecta gravel was placed to serve as a breeding habitat. The slotted uptake pipe pulls water from between the gravel to create excellent water quality that is needed by metabataeus.
We stocked it with 50 opae-ula and initially most stayed in the gravel habitat. About 2-3 months later, we began to notice tiny juveniles walking around at the base. Then we introduced 4 metabataeus and the dynamics changed! Now the metabataeus is usually in the habitat and the opae-ula are outside. At one time they were clinging to the tank walls but are now usually on the constructed lava formation.
Visitors enjoy watching the interaction!
|The tank makes a great opae-ula photo studio! When the lights are off, you can barely see the opae-ula. But with the lights on, visitors are immediately attracted to this tank! This photo was taken with a standard digital camera at the "close-up" setting and taken of the right side of the landscaped cliff.|
|This photo taken on the left side of the tank with a number of opae-ula. In healthy ponds, you will often see opae-ula at about this density.|
This photo, shows a metabataeus which has
grown larger and is now well over twice the size of the opae-ula. It is very
aggressive and is clearly an opportunistic omnivore. Metabataeus has a
keener sense of smell and will notice when spirulina is floated on the
surface before the opae-ula. It is shown
with it's reflection filter-feeding at the surface.
Opae-ula tend to stay clear of it when its around and the metabataeus feeds first, feeds until it's satisfied, and seems to prefer spirulina over opae-ula. We theorize that if we feed generously, that the metabataeus and opae-ula will co-exist and the opae-ula will again reproduce and increase.Our first mixed tank was set up initially to test creating a opae-ula breeding habitat behind a vertical lava cliff with aggregate encased between the cliff and the back of the aquarium.
|Another photo of the metabataeus filter feeding with an opae-ula behind it. Metabataeus is twice as large with a large black mark and a more yellowish color. It has prominent white bands at its tail joints.|
|When a metabataeus is filter-feeding, the opae-ula stay clear of it. But after a while, they sense that the predator is less hungry and less likely to attack them. So they begin to filter feed also.|
|After a while, the metabataeus is again hiding in the gravel habitat and the opae-ula continue out in the open. Some opae-ula simply hang on to a rock while eating the floating spirulina. Others swim up to the surface to filter-feed for a while and come down to rest. After digesting it for a while, they swim back up to the surface. When properly fed, all food is consumed within one hour and the water quality remains high.|
By observing how opae-ula react in different environments, I get a deeper understanding of their natural personalities and characteristics. I believe that opae-ula from different places and different types of environments have different personalities and characteristics.
At Fuku-Bonsai, most of our research tanks contain only opae-ula that we've obtained from one area which has proven to be very tameable. We also have tanks of opae-ula from different places and some are very difficult or impossible to tame. Some researchers believe that opae-ula grown in areas with a large number of metabateus are under a lot of stress and therefore more difficult to tame. But as you can see from the above photos, metabataeus and opae-ula CAN CO-EXIST! The next section tells of setting up an experimental tank for the metabataeus and opae-ula from the Pohiki Pond.
*** Continue to POHIKI OPAE-ULA & METABATAEUS MIXED TANK