You may have memories of running after fireflies with hands outstretched on a warm summer evening. You may have even watched some discovery channel documentary on the mysteries of the deep sea and marveled at those 'glowing' organisms featured. Chances are however, you probably haven't heard too much about the plethora of other bioluminescent creatures inhabiting this planet.
Bioluminescence (literally meaning living light) occurs within many living organisms, although, most are relegated to the deep sea. This chemical reaction involves the oxidation of Luciferin (just a name for a class of biological light emitting pigments). While related, the name doesn't come from any devilish origins, but rather the latin 'lucifer' meaning "light bringer".
Depending on the organism, the light can be used for camouflage, attraction, or even communication among bacteria to name a few. Some of the more notable organisms that bioluminesce include fireflies, glow worms, bacteria, a plethora of marine life, and even mushrooms. (Here's a favorite video of mine from planet earth on the glow worm http://www.youtube.com/watch?v=kBIEmjaoE5w)
Today however, we'll focus on a particular light emitting alga known as Pyrocystis fusiformis. These dinoflagellates typically do not occur in high enough concentrations among marine algae to produce a very noticeable glow. However, when the conditions are right (excess nutrients, enough sun, etc) an algal bloom can occur and populations explode. Chances are you've heard of this phenomenon before which (albeit not involving this particular organism) is also known as a Red Tide.
Here's a video of one such concentration in a bay in australia. They are simply throwing water into the bay as the algae only luminesce when disturbed. A popular theory is that the light is used to attract predators of the grazers of dinoflagellates. Case et al. (1995) demonstrated that the feeding rate of squid of mysids in the dark increases significantly when bioluminescent dinoflagellates are present.
There is even a bay in Puerto Rico full of the stuff which people can kayak in. http://www.biobay.com/
With a little luck and a LOT of patience, you can grow your own bioluminscent algae at home.
Step 1: Gather the Materials
A number of marine enthusiasts already grow phytoplankton at home for use in feeding various species of marine life. The method we'll use is rather similar.
To start, you need,
-A clear growing container (shallow containers with lots of surface area work best)
-A grow light and timer
-Micro Algae Grow
-A Starter Culture
Sea Salt: No, not from your pantry you gourmet fiend, you can get this at most pet or aquarium stores.
Grow Light: you can pick up a plant fluorescent and rack from walmart for ~$10.... Make sure you have a light timer.
Micro Algae grow: our most crucial ingredient. (besides the actual algae) There are a number of nutrient formulas people have experimented with, and truthfully, I've only had mixed results with this one. Experiment with what works best.
A Starter Culture: These can be obtained from a few places online. I recommend www.empco.org/edu
Step 2: Preparation and Mixing
Sanitation is necessary so your batch doesn't crash. After you REALLY wash out the grow container, make sure there is absolutely no residue left. Some people say swirl some diluted bleach around. Others say to stick it in the microwave after it's completely dry (won't melt or deform if it's dry... wet is another story). Choose your preference.
Additionally, sanitize the tubing if you're using an air pump, and anything else you're using to prepare this batch.
Mix up a batch of salt water. Use purified water as tap water can contain chlorine or other things that might kill your batch.
Mix the salt to a 1.019 specific gravity (sg) concentration. Directions on how to do this are on the back of the package... you'll need a hydrometer if you've never done it before.
Add in ~ 1 ml of the micro algae grow. In this case, less is more. The solution you received the culture in should already have enough nutrients to support sizable growth. If you don't want to mess with making your own solution (not necessarily a bad idea) many places that sell starter cultures will also sell culture solution.
Let both the solution and culture bag sit in the same area out of the sun for an hour or two. This is simply to let them reach room temperature. A sudden change in temp during transfer could shock the culture enough to significantly harm it. If your room temp is in the 70s (F) , you should be okay. Ideally, the water should be around 22 degrees Celsius.
Finally, transfer the algae into your bottles. Attached is a picture of a grower's setup. (Your bottles won't be green though)
Step 3: Growth
These dinoflagellates need a constant cycle of light and darkness for optimal growth. Put your grow light and bottles in a dark place (closet) where you can strictly control how much light they get. Set the timer so the grow light is on a cycle of 12 hours on, 12 hours off. Don't be worried if your starter culture doesn't emit light right after you receive it. They will only bioluminesce in their night cycle, so plan the light cycles accordingly for when you want to see it.
Monitor your cultures for any sudden changes in color, and give them a gentle shake every day or so or all the sediment will collect to the bottom. If you have a successful culture, you will eventually need to 'split' the batch. Mix up another batch of saltwater/nutrients, and halve your culture between the new bottles.
Remember, these cool creatures will only brightly flash when disturbed and only during their night cycle. Too much disturbance can both harm them,and wear them out. They have a 'recharge' time so to speak between disturbances for optimal performance.
If you're looking for something which will constantly glow, you might want to check out bioluminescent bacteria instead. You can get some from Carolina Biological supply. Culturing this is a rather different process, but you can find some guides on the net. One bioluminescent strain is Vibrio fischeri.
The pictures on this page are not mine and are mostly from this site: http://www.biology.pl/bakterie_sw/bac_pict_en.html
Good luck and have fun!