karimwassef
Active member
Calcium based - aragonite, oolite, coral rubble
It was a controlled DSB experiment... it just doubled as a cryptic zone
It was a controlled DSB experiment... it just doubled as a cryptic zone
So if I go on the algae scrubber threads, there is a very specific few ways of doing things. There are formulas to adjust the ATS to how much you feed.
So, say I wanted to make, rather than a refugium or ATS, a cryptic sponge refugium or even a sponge scrubber. What are the optimal conditions I can provide to grow sponge biomass?
As another note, if I wish to make this area view-able, is there a way to make it look nicer? Some of the sponges I have seen growing in a local reef DT are bright orange and encrusting with GSP. Super cool.
I saw one the other day that had a tank covered in black plastic square panels.
The front panel was removable, to reveal an attractive display with some neat sponges.
Wertoiuy's questions triggered a thought: it might be useful to net this out in a simplified manner that is easily digested. Let me see if I can do this without offending anyone...
"Cryptic zones" and "algae scrubbers" of various types serve different purposes and one is not a good substitute for the other.
An algae scrubber has the following properties:
- Requires light and works best with strong light and moderate to strong water flow.
- When the light is on, it absorbs carbon dioxide and releases oxygen, raising the pH and increasing oxygen levels in the water.
- For growth it absorbs inorganic phosphorous and nitrogen, along with small amounts of other elements such as iron.
- A successfully set up scrubber will produce large quantities of excess algae, which can then be removed from the system. That makes an algae scrubber an efficient mechanism for export of surplus nutrients.
- Some types of algae make good fish food.
- Algae will "leak" organic materials into the water, which may be undesirable. This depends somewhat on the species of algae.
A cryptic zone:
- Works best in the dark (thus, "cryptic") with low to moderate water flow, depending on the species grown. Requires little or no electricity.
- Captures and digests various organic particles from the water, including bacteria.
- For growth, some of that material will be incorporated into the bodies of the cryptic organisms. However, growth tends to be slow compared to algae, so this is not a very efficient mechanism for nutrient export.
- Will excrete various organic and inorganic "wastes", some of which can be good food for other desirable organisms in the system, such as corals.
In effect, algae are a good export mechanism and cryptic organisms are a good recycling mechanism. You might want an algae scrubber if you have excess nutrients that need to be exported, particularly in a heavily fed system. You might want a cryptic zone if you want to make more efficient use of the nutrients in the system, independent of whether you need an export mechanism.
I liked the overall generalization. What was glossed over was the leaked DOC from algae. The DOC from corals is rich in proteins & lipids but the DOC from algae is rich in carbohydrates. The equivalent of junk food for your reef tank. The use of GAC or cryptic sponges rectify this issue.
The sponges in cryptic refugiums are all about recycling DOC into dissolved inorganic carbon and Marine Snow, both of which are food for corals.
Generalizations are running rampant. All photosynthesising organisms produce carbs. The fleshy algaes are the ones that produce al lot of exudates, containing carbs. The algaes typically used for filtration don't exude all that much of anything into the water. :beer:
I tried to search a bit for descriptions of what algae gives off. Didn't find much, and would love to read details if anybody digs up what sorts of things are given off by common aquarium algaes. Chaeto, caulerpa, and turf scrubber stuff.I have not seen the list, but from previous discussion on this thread, chaetomorphy produced the least.
What algae do you use on your turf scrubber?
I have not seen the list, but from previous discussion on this thread, chaetomorphy produced the least.
What algae do you use on your turf scrubber?
Live rock cryptic zones have always been interesting to me.I recently started reading Steve's books. Anyone else interested in this topic?