Coral Breeding tank

[Cjvolitan]

Hello guys it's your old freind from Trinidad, i know i have not been on here for a real long time but i need your help. I nned your advice on seting up a system for keeping coral that ill allow for the settleing of coral larvae and for keeping Zooxanthelle on there own out of their coral host. I know this is a bit technical so i'm hopeing some one ( Jake Adams are you around? )
can help me with this. Oh and it's all for a school project

[Rob]

hey, glad your back around..
sorry, this is way out of my league, but i will notify a few people that might be able to help

[coralite]

Hey Volitan,
I think I can help you out. Please let me know what coral species you are working with. Also, can you elaborate on what you want to do with the zooxanthellae?
Jake

[BrianPlankis]

Jake is the expert here, so I will defer to whatever he tells you, but I wanted to let you know that we will be looking at breeding corals at Project DIBS starting in Feb/March of this year. We will have some of the procedures, adapted to hobbyist tanks, listed in the two coral breeding challenges we are going to attempt:

2007 Breeder Challenge #1: Manicina areolata (Linnaeus, 1758)

2007 Breeder Challenge #2: Pocillopora damicornis (Linnaeus, 1758)

I'm looking forward to what Jake says as well

Brian

[Cjvolitan]

Thanks alot guys
okay jake i want to try to cultivate and settle out the larvea of Diploria strigosa the symmetrical brain coral, and elkhorn coral Acropora palmata.
What we plan to do is isolate the zooxanthellae from the coral species above and then see if we can culture them externally in a separte tank away from their coral host.I'm not shure if this is even possible but hey thats what reserch is about right.
I'm also looking forward to what you guys are doing over there at project DIBS brian.

[Rob]

Erik from algagen might have some insight on the zooxanthellae part, let me message him

[Cjvolitan]

Thanks alot Rob.
The community has been a great help.will try to get some shots of the setup once iot's up an running.

[AlgaGen]

There are a number of clades of zooxanthellae not all have been successfully cultured. I am not an expert on this either but in quickly reviewing where some of the clades in culture have been isolated from, the hosts, and the recommended growth media, it looks like zooxanthellae isolated from corals(mostly) grow on f/2without silica-normal microalgae media- whereas those clades isolated from clams or anemones require a sugar added to the media. The link below is for an alternative media called K and you can find the media recipe for the f/2 without silica as well. I believe that these guys also sell pre-made media.

(CCMP - The Provasoli-Guillard National Center for Culture of Marine Phytoplankton)

There are a number of clades of zooxanthellae that have been isolated. How do you plan to isolate the zooxanthellae? Are you going to have the isolated zooxan identified? Do you know what clade you should be getting? There may be some in culture all ready and all you would have to do is purchase a starter culture.

[Cjvolitan]

thanks eric i will check that out

[iglowce]

welcome back!

[coralite]

Once you get your egg bundles from either species, you will have to give them 10-20 minutes to break up into eggs and sperm, probably less time by the time you get back to shore. I know that palmata will not self fertilize so you will have to get egg bundles from at least two separate colonies and make sure that they are far enough apart that there is a low likelihood that they are clones. Once your egg bundles break up and you have thoroughly mixed them all up in the same container (per species), give them about at least 1-2 hours to simmer with occasional gentle stirring. After that time, you will need to gently rinse off the still buyoant newly fertilized eggs several times to wash out the sperm. Before rinsing the egg-sperm water will be cloudy but when the rinses have washed off most of the sperm the water will become clear. If you do not rinse the egg-sperm water there is a risk that some eggs will be fertilized multiple times (polyspermy) which will result in unviable dead eggs.

[coralite]

The following image shows a diploria which is releasing egg bundles. The tissue becomes very swollen and there is an unusually clear distinction between sexually active and inactive tissue.

In Puerto Rico, palmata begins to release egg bundles around 9 oclock and diploria starts around midnight. When the broadcast spawning event draws near, there will be many postings on the coral-list about approximate spawning dates and time for differetn regions. the spawning nights will be long work for you and you will likely not hit the sack until 2-3 am.
The next morning you will have some rapidly developing embryos and you will need to determine the cleavage state and the fertilization rate. Healthy embryos will be full and round and inviable eggs will appear collapsed and they will begin to disintegrate. the following image shows a sample of palmata eggs the morning after spawning and the inset illustrates the difference between good and bad eggs.

[coralite]

Once your embryos have been rinsed free of the inviable and dying eggs and debris, place them in a clean sterile container where you intend to hold them until they are ready to settle out.
The larvae tend to collect at the surface and along the sides of the container so it is important to pick a vessel with steep smooth walls. Since the larvae collect at the surface it is also advantageous to select a vessel which is shallow with a large surface area.
At this point there are two routes you can use to raise your embryos to larval hood.
You can raise them manually in an unfiltered container which will need to be agitated fairly often and which will need to have manual water changes 2-10 times a day, depending on the conc. of your embryos/larvae. This method has a high success rate but it is very labor intensive, especially right after the spawn. As the larvae grow and metabolize their fat they can foul the water very rapidly.

the other method is to grow larvae in flow through vessels. for this method I opted to design a very large filtration sleeve with nytek nylon filter material covering a cylindrical frame. 100um should work well for both species. Since palmata larvae are 300um long it is tempting to use 250um screen for their containers but this is not advisable. with 250um screen palmata larvae will get stuck in the mesh making them very hard to remove and smaller larvae and embryos will slip through. Besides, diploria eggs are in the 150um range so if you confuse your mesh sizes you will lose alot of larvae. the following image shows one of the conatiners we used for raising palmata larvae.



Well in advance of the spawning event (2-3 months) you should place your settlement substrate of choice (preferably limestone tiles or something similar) on a clean healthy reef where some biofilm and crustose coralline algae can grow and cover the settlement substrate.

sorry for the poorly organized post but I just wanted to post something while I had the time. I have more to say about innoculating the larvae, maintaining the larval vessels and finally the settlement but I have to go to work now so I will post more as soon as I get a chance.