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To survey Articles on: Invertebrates, Ascidians/Sea Squirts, Sponges, Live Rock

Book Review:

The Environmental Gradient

Cryptic Sponge and Sea Squirt Filtration Models, 2d ed.

Volume 1 of the Captive Maintenance Advanced Techniques CMAT Series

Steve Tyree

288pp, Softbound, $33.00 plus shipping (see site below)

2000, D.E. Publishing

8976 Foothill Blvd. B7, PMB #299

Rancho Cucmonga, CA 92730


Bob Fenner  

Steve Tyree continues in this updated version in his CMAT (Captive Maintenance Advanced Techniques) to, in his own words, "examine the leading edge and advanced techniques utilized to maintain captive ocean organisms". As a completely self-produced work (writing, images, graphics, lay-out…) this is an admirable work of some new and important ideas in aquarium set-up and operation.


This is an account of Steve's personal odyssey in keeping and culturing attempts with different groups (cnidarians, sponges, ascidians) utilizing simple, readily available gear and tools. To his credit he has pursued and developed his concepts through experimentation and delving into the scientific and engineering literature. What we have here is a historical relating of Steve's attempts (not always successful) at devising and understanding the utility and processes of cryptic organisms (particularly poriferans/sponges and tunicates/sea squirts) in the wild and in captivity.

The Good:

Even casual divers and folks handling live rock can tell you of the prominence of these cryptic organisms and their biotopes. The living component/matter of so-called Live Rock is made up more of Sponge material than any other phylum of life. Some places in the oceans the Sea Squirts are obviously populous, though most are inconspicuous or hidden under dark spaces. There are speculations that in the tropical West Atlantic, that the sponge life passes about the entire volume of water through their bodies every few days. That their presence is important in living systems in situ and captivity should come as no surprise.

Steve makes a plausible argument that instead of Berlin Systems, utilizing Live Rock and skimmers, that folks might instead be better off using heterotrophs as and associated with sponge and sea squirt life, as these use the "same" organics as skimmers remove.

You have an inkling of the failure of current trickle filter designs? Good, Steve and I do too. Somehow George Smit et al.s designs from the mid eighties lost their purposeful denitrators. This is covered here.

The Not-so-Good:

Steve needs an editor, big time… he reminds me of so many of my "educated-derelict" friends from college it's painful. He has good ideas, an enterprising mind… but the sentence structure, spelling and word usage here is atrocious. The relating of experiments… designs, results shines… it's the trying to understand the sentences that will bother many readers.

Some general statements are unsupportably sloppy: p.34: "The water is kept anoxic with 1 ppm oxygen and is not allowed to become completely devoid of oxygen". The term "anoxic" needs replacing with "hypoxic".

The books layout, introduction and logical presentation of concepts is laudable, and illustrations nice, but the photographs and their reproduction here on the cover and the books middle are terrible.

Conclusive Remarks:

The basic premise here of the importance of cryptic organisms and their potential as overall moderators, maintainers of water quality in captive systems cannot (at least not by me) be disputed. Steve does a good job of making his arguments on this point, but would do well to have a good editor assisting in making them clearer.

Steve states: "This book contains the foundation for a new zonal approach to maintaining tropical reef organisms. Captive reef aquarist(s) and reef scientist(s) can utilize this zonal approach to enhance the diversity of organisms maintained within captive reef systems." For the purposes of reviewing filtration methods, seeing how Steve "did it" (trials, tribulations of isolating his cryptic assemblies, keeping the light and predators off of them…" this book and its series are well worth the effort for advanced reef aquarists.

55 Gallon Non-Photosynthetic Tank Hey guys, I'd just like to ask a few questions about some issues that I have been having trouble finding any information on. As the subject says I will be starting a 55 gallon non-photosynthetic tank in a few weeks. I will be building everything myself including my own Aragocrete rock. I will be using a phytoplankton reactor to constantly drip a freshwater Nanochloropsis culture into the tank as top-off water, so as to provide a constant food source for the corals. I will not be using a protein skimmer because I want a high nutrient level in this tank. So to assist in filtering the tank without a skimmer I will be using an environmental gradient system in the tank and creating a cryptic zone populated by sponges, tunicates and bi-valves that will use dissolved organics and phytoplankton for nourishment. The tank itself will have a strong flow but the cryptic zone will have a very diffused and much slower flow, it will also have limited entryways to prevent large particulate matter and detritus to building up inside. I have been doing as much research on the subject of environmental gradients and trizonal filtration as I can find online, but I am having trouble finding more information since it is still a mostly unused concept in reef keeping. <Mmm, please read here: http://www.wetwebmedia.com/tyreecmatv1.htm> This tank is going to be populated by a variety of carnations, tube corals, gorgonians, sponges and feather dusters, most of which are noted for being difficult to keep in a reef system. I believe my elevated nutrient levels should provide a good home for these corals and I'm just looking for any information that anyone can provide. Thank you for any input.                                                                                                     Mike Janosko <As you will see, by reading my brief review to Steve Tyree's book/s... there is substantial input to be had by searching here... A worthwhile project... easier to do in larger volumes. Bob Fenner> Steven Tyree It is to my understanding, after talking to someone at Fama, that you might be able to help me find the lastest book Enviromental Gradiance by Steven Tyree. If you can help me, would you please contact me at (276)688-XXXX. thank you! Sincerely. Mary Sivert <Thank you for writing. Sure enough, Susan Steele left me your name, # just yesterday. Steve's self-publishing biz, and a review of this work can be found here: http://www.wetwebmedia.com/tyreecmatv1.htm Be chatting. Bob Fenner>

Cryptic filtration  6/21/10
I did not see any articles on cryptic filtration.
<Oh yeah... I wrote a review of Steve's "book/report" on the topic back in 2000: http://wetwebmedia.com/tyreecmatv1.htm
I have heard of an individual, Steve Tyree, and the topic of a natural cryptic zone aquarium with low flow for filtration purposes. What are your thoughts or suggestions on this?
<Is of use, interest>
I was looking to set up a 20g long, 30g breeder, or 40g breeder as a cryptic tank to use for natural filtration.
<Welcome. Bob Fenner>
Re: Cryptic filtration  6/21/10
Thank you for your quick reply. I read your review and looked for the book, but it is out of stock (print).
<Ahhh, as I hinted at, this was more like a "review" of others work... actually a print out verbatim of sci. journal pc.s, w/ some brief notes from Steve following...>
Is it basically that I need to put a little sand in the bottom, some rubble or <and> live rock and run a low flow of water through the tank, which will over time begin to grow a cryptic zone?
<Along w/ a lack of light, this is about it. B>
Thoughts or suggestions.
Thank you,

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