I moved this out of the "Blue crabs in a tank" section so others who might be interested would see. The subject is the use of sponges and sea squirts as living filters for aquariums in a blacked-out refugium.
The best information on sponges and sea squirts I've found is in the http://www.amazon.com/Reef-Invertebrates-Essential-Selection-Compatibility/dp/0967263034/ref=pd_bbs_sr_1/002-2168722-6716052?ie=UTF8&s=books&qid=1192111802&sr=8-1">Reef Invertebrates</a> book and [IMG]http://www.amazon.com/Reef-Aquarium-Science-Technology-Vol/dp/1883693144/ref=pd_bbs_2/002-2168722-6716052?ie=UTF8&s=books&qid=1192111802&sr=8-2">The Reef Aquarium Vol 3</a> goes into some detail regarding techniques of creating a black-out "sponge filter" which is often referred to as an "Environmental Gradient" system or a "Cryptic Fuge". There is also a video podcast on a [IMG]http://www.talkingreef.com/forums/podcast-episodes/3413-diy-cryptic-tube-fuge-video-podcast-episode-88-a.html">DIY Cryptic Tube Fuge on Talking Reef.</a>
If anyone's interested in this idea, here's a [IMG]http://www.dynamicecomorphology.com/">website</a> I found that has some details and sponge packages for sale. Of the LFS I frequent, I know that Cap Bay has sponges and I think I remember seeing some at Marine Fish. The most important part of sponges is to never expose them to air, if at all possible. This can trap air bubbles in their structures which can kill the sponge.
The idea is to provide a light-free area where you can encourage sponges and sea squirts to grow. Odds are, unless you're running an almost nutrient-free water column or have a very young tank, you've got some already somewhere in your tank. Probably in a dark area of the rock. By providing a light-free environment which can be a PVC tube, a blacked out tank, a Rubbermaid tub, or a HD/salt bucket, you eliminate competition from algae (both coraline and nuisance).
The best information on sponges and sea squirts I've found is in the http://www.amazon.com/Reef-Invertebrates-Essential-Selection-Compatibility/dp/0967263034/ref=pd_bbs_sr_1/002-2168722-6716052?ie=UTF8&s=books&qid=1192111802&sr=8-1">Reef Invertebrates</a> book and [IMG]http://www.amazon.com/Reef-Aquarium-Science-Technology-Vol/dp/1883693144/ref=pd_bbs_2/002-2168722-6716052?ie=UTF8&s=books&qid=1192111802&sr=8-2">The Reef Aquarium Vol 3</a> goes into some detail regarding techniques of creating a black-out "sponge filter" which is often referred to as an "Environmental Gradient" system or a "Cryptic Fuge". There is also a video podcast on a [IMG]http://www.talkingreef.com/forums/podcast-episodes/3413-diy-cryptic-tube-fuge-video-podcast-episode-88-a.html">DIY Cryptic Tube Fuge on Talking Reef.</a>
If anyone's interested in this idea, here's a [IMG]http://www.dynamicecomorphology.com/">website</a> I found that has some details and sponge packages for sale. Of the LFS I frequent, I know that Cap Bay has sponges and I think I remember seeing some at Marine Fish. The most important part of sponges is to never expose them to air, if at all possible. This can trap air bubbles in their structures which can kill the sponge.
