Tuesday, November 22, 2011

My plans for the future.

So I feel I haven't touched much on what I'm currently doing or what projects I'm planning for the future.

Right now I'm working on a major project through my school on growing moon jellyfish. I'm taking the class "Biotech I", and we have a semester project due in january. Im working specifically with polyp cultures and ephyra. Since I've been such a failure with growing the ephyra, I've begun to try some new methods. I have access to a huge amount of equipment and tools to help raise these ephyra. Some particular things that caught my eye were, the magnetic stirrers, water baths, incubators shaker tables, etc.

My first experiment was finding out whether the stirrer or the shaker table worked better. Over a course of two weeks me and my team felt the magnetic stirrer was showing much more positive results. The shaker table was on its lowest setting and still ended up beating the ephyra around and deforming them. The stir plate was set at 65 rpm and kept the ephyra up and moving in a good motion.

An experiment my friend did caught my eye. I let him use 5-10 ephyra for an experiment. He brought back a two liter bottle of ocean water and sand from myrtle beach, and requested to grow some ephyra in it. In my mind I thought this was a terrible idea. This bottle had been sitting, capped with no air or sunlight for around a month. The ephyra would have no circulation and would be lying in a sand bed. surely they would die. But they didn't die. They showed fantastic results, and grew much faster that any ephyra I have worked with. They are still growing as of right now. I thought for a while, as to find an explanation for this. I noticed the jellyfish were constantly feeding on this brown substrate at the bottom. it must be a mixture of algae, bacteria, micro crustaceans, and fish waste. The bacteria, algae and micro crustaceans must be supplying them with a good source of food. Perhaps the ephyra didn't mind growing up on sand. They probably end up on sand a lot in nature. the tentacles don't have a solid surface to stick to, therefore the issue of tentacles sticking and rotting is eliminated. The bottle is now being aerated as well. So to mimic these great results I'm going to buy some real ocean water from the pet store and inoculate it with the beneficial bacteria and organisms from the beach water. Perhaps I can achieve some better results this way. I will also be sure to post my results here, they could be very helpful for many people.

I have a few projects in mind for the future. Some time after christmas I'm going to be ordering several cannonball jellyfish and a comb jellyfish or two. I really like cannonball jellyfish, and I want to study their behavior. I also want to obtain some polyp cultures from them. I have a 55 gallon tank I plan to put the cannonball jellies in. I figure that should be around enough room for four or five cannonball jellyfish. I will just build a simple overflow to drain the water down into a sump and filter it there. Cannonball jellies are really strong and will have no issue with being sucked up into an overflow. Thats one reason I like them :)

Cannonball jellyfish (Stomolophus meleagris) with several small fish trailing behind to capture food. 

The comb jellies are a  different story. They are extremely delicate and they will need to live in a kreisel tank. I plan to just convert a 10 gallon tank into a kreisel with a plastic sheet, some acrylic and a screen. These particular comb jellyfish (Mnemiopsis macrydiare bioluminescent and display a cool refraction of light on their cilia. Apparently most comb jellyfish contain both male and female organs and can reproduce on their own. So I may try to culture a few comb jellies.

So thats what I'm up to right now. Hope you are looking forward to my upcoming projects. Feel free to email me for help or general questions about jellyfish, at [travis.brandwood@gmail.com]

Picture credits~

  • http://www.tnaqua.org/Libraries/Invertebrates/Sea_Walnut.sflb.ashx
  • http://3.bp.blogspot.com/_BLysnmXIPfM/S_7J988H8fI/AAAAAAAAAVw/1QzdkTJuj30/s1600/stomolophus+community.jpg
  • http://www.aquarium-design.com/invert/40.jpg

Saturday, November 12, 2011

Dealing with hydrozoans.

Hydrozoans are one of the nastiest creatures that could invade your aquarium. Once they are there its very difficult to remove them. They spread very fast and may take root all over your tank.

Hydrozoans may not affect your tank negatively. Some jellyfish get along with hydrozoans. Often times, however, your jellyfish will not coexist with the hydrozoans. This means they must be removed before they overpower and kill your beloved jellyfish.

The most straightforward method of removing hydrozoans is to bleach your tank. Depending on your tank type this may be a simple task or a difficult task. Kreisel aquariums are relatively easy to bleach. Just shut off water leading to and from your sump area. Take out your jellies and anything you wish to not bleach. Then add bleach to the water. the amount depends on the size. The bleach should kill off everything in the tank. De-chlorinator should be used to neutralize the bleach. I'm currently unsure as to how much dechlor you should use, but it is proportionate to the amount of bleach you use. Now, bleaching your tank will only kill the hydrozoans in the tank and not in the full system. You would have to bleach your sump as well, which would kill off all the beneficial bacteria. If the hydrozoans become a problem then you may have to do this.

Having a smaller 9 gallon cylindrical tank may be more difficult or easier depending on how you look at it. You will pretty much have to nuke your whole tank with bleach. They hydrozoan hydroids attach themselves to the substrate and that will have to be bleached. Sadly that means getting rid of your colonies of helpful bacteria. These colonies may grow back fast since there is the same bacteria living inside your jellyfish. So just move your jellyfish and other live material (snails, crabs, fish etc) into a safe holding tank. You can just put everything in a rectangular glass tank until you finish bleaching. scoop out the marbles and then the ceramic media. Put them into two separate bowls. Trust me, keeping the two separated save you and hour or two of sorting out the marbles from the rocks later on. Add about a cup of bleach to the empty tank. As for the substrate, wash both the marbles and rocks (separately!) in a strainer with very hot tap water. The heat, chlorine, and fresh water will help kill the hydrozoans. Then you can bleach the media or boil it for an hour or so. Just make sure that ceramic rock is really soaked. It's very porous and small hydrozoans may take refuge in those pores and then return in your tank.

Once you are sure your tank and substrate media has been sterilized, you can return everything to the tank. Personally I would drain all the old water out and wash everything then get new saltwater. I feel a good wash of everything will remove dead hydrozoans and will give your tank a fresh new start.

Bleaching should leave you with a hydroid free environment, assuming you eliminated their source of entrance as well. Hydroids can come from a variety of sources and you should make sure you don't introduce new hydrozoans into your tank after you go through the suffering of bleaching your tank. These sources may include~

  • Brine shrimp eggs.
  • Hermit crabs. 
  • Ocean water that has not been sterilized.
  • Live rock/live sand.
  • Things bought from major pet shops. 
You can eliminate hydrozoans from brine shrimp eggs by getting decapsulated brine shrimp eggs. These are eggs that have been bleached to have the shell removed. Some varieties of these eggs will still hatch, and get rid of the hassle of separating the hard brine shrimp shells from the shrimp. They are also often free of hydrozoans. just make sure your supplier specifies that they are sterilized and also still hatch-able. 

Try not to buy hermit crabs or fish/ invertebrates from major pet dealers. Buy from reputable fish stores. This may help eliminate hydrozoan introduction.

If you want to use real ocean water then you should sterilize it first. Otherwise, using manmade saltwater works just fine.

Sand and live rock aren't often used in jellyfish aquariums since only certain jellyfish can tolerate sharp objects in their tank. Jellyfish art's tank uses live rock as filtration. The tank comes with dry ceramic media containing no life. They some live rock with every purchase of jellyfish. So there is no need to add any live rock which could introduce hydrozoans to your tank.

Monday, November 7, 2011

A Jellyfish Emergency; When Hydrozoans Attack!

Hydrozoans are like the bad cousins of jellyfish. They can deplete your tanks nutrients, cover your tank walls and most importantly, damage or kill your jellyfish.

Earlier this year in march I witnessed a major hydroid attack on my jellyfish. I had no clue what was going on, as I was not expirenced. All I could understand was that something was making my jellyfish very sick. I did nothing to stop the undetected attack and my jellyfish died. My three jellyfish began acting very strangely. They slowed down and began to become very soft and gooey. Obviously moon jellyfish are already gooey, however it seemed like my jellyfish were beginning to melt! The jellyfish spent their time stuck to things such as the substrate or sadly, even the heater. Eventually the jellyfish withered away like a block of melting ice, leaving me with several questions. The tank was empty except for a snail and two hermit crabs. I began to notice this intricate spider web design on the acrylic near the bottom of the tank. I was searching for polyps, and at first I thought I found them, however I later realized that I ran into hydroids.

Hydroids are simply the polyps of hydrozoan jellyfish. They live in a network style colony, forming branches with little buds at the end of the branches.

I watched these strange hydroids for a while, and to my surprise they began to produce small jellyfish. These new jellyfish were very strange. They were very simple and didn't do much. In fact they pretty much latched onto the walls of my tank and stayed their until something disturbed them. They didn't get very big either. At times I would have 20 or 30 of these things. And then their populations began to decrease. They were draining my tanks food and I didn't feel like replenishing it. Then of course I ended up knocking my tank over, and wiped out their population.

A video of some hydroid jellyfish found in my tank in march. 

Im sure your thinking this is a nice story and all, but why? Well I realized yesterday that their are hydroids present in my tank again. I think they hitched a ride on my clown fish and were accidentally introduced. My first thoughts were to nuke the tank with bleach. But then I began to question that. nothing in my tank is any different. My jellyfish are healthy, as are my clownfish and snails. These hydroids may produce jellyfish, and possibly a new jellyfish Im unfamiliar with. So I decided I would attempt to remove them and grow them elsewhere. Well I scraped as many as I could see off, and put them in a flask. They grew back almost immediately in the tank. The colony still seems small though, and there is no sign of any hydroids gearing up to produce jellyfish. They just seem to be busy eating. in fact not all hydroids produce jellyfish. These may just stay hydroids. However I hope that they produce something cool while they loiter in my tank.

So I'm just going to watch the colony and intervene if something goes down. My next segment of this will be on the removal of hydroids and what you can do about them.

Picture credit~

Saturday, November 5, 2011

Stage V: The free swimming ephyra and juvenile Jellyfish

The fourth stage is the ephyra. This is the first stage where things start looking like jellyfish. Ephyra generally pulse off the strobila looking like little star shaped jellyfish. They generally eat rotifers or baby brine shrimp. Once they begin to grow bigger they fill in their flesh, so that they appear more round. The also begin to grow a stump, and then full oral arms.

Once the ephyra get bigger they pass into the juvenile stage where their bell measures 1- 2 inches in diameter. At this point they can breed amongst each other. The jellyfish will continue to grow if fed well. Moon jellyfish can get very big in their adult stage, up in the 12 inch diameter region!

Thursday, November 3, 2011

Stage III: The Polyp ad strobila.

Once the planula has found a good, solid surface to attach to, it will metamorphose into a polyp. This stage is fairly stable, as the polyp doesn't do much, nor does it move.

A polyp is essentially a small bud and stem, very much like an anemone. It has a large mouth compared to the body. When capturing food, it will sting the food material then retract its tentacle so the food comes flying through its mouth into the polyps oral cavity. When the polyp is hungry it is very easy to see its tentacles mouth an oral cavity under a microscope.

Polyps have to complete several tasks. Polyps have to eat, so they will extend their tentacles and open their mouths wide open. Polyps can also produce more polyps by budding off asexually, leaving you with two polyps. The third thing polyps will do is transform into a strobila. When favorable conditions occur, such as temperature  spikes or drops or perhaps higher iodine levels, the polyps will begin to elongate. This means that they literally begin to get long and skinny. Then, the polyp begins to look bumping with ridges going up and down their upper region. These ridges get deeper until the polyp looks like a stack of discs. Each disc will eventually be a jellyfish. The discs begin to pulse as the near the end of their maturation. Then they will pulse off and swim away. This stage is known as the ephyra, and is the next stage in the life cycle.
Two small polyps and a strobila are shown here in a petri dish, feeding on brine shrimp. 

This whole process of polyps making jellyfish is known as strobilation. The interesting thing here is that the polyps will go back to being regular polyps after the strobilate. They can produce hundreds to thousands of jellyfish in a lifetime under perfect conditions. So polyps can produce tons of ephyra and also make asexual copies of themselves. This means that if you have a few polyps you could theoretically have an infinite source of jellyfish as long as you don't let the polyp colony die. This is why I feel the polyp stage is the most important.
A strobila under 10x magnification. Notice the clear stacks of disc shaped ephyra.