REALLY cooking rock

Well. This is the discussion I've been wanting to hear for over 2 months since I heard about boiling rock. The rock boilers discussing the merits off methods of P reduction with the rock cookers.
Dead, boiled and bleached coral skeletons are not very effective denitrifying filters.
Under the BB method as I've read it, I don't understand why not. The only organisms doing any effective work are bacteria. Why even bother with boiled coral skeletons? Inert glass or ceramic with a fine, open pore structures should function the same, right?

My perspective is P in rock (or sand) isn't the problem its made out to be. So I grapple to understand the perspective of people who think it is. The logical conclusion to your argument - to me - is just to avoid organic-derived media altogether, and just use a synthetic one.
 
So Howard. Ceramic is phospate free? Any other elements there that could be detrimental? Seems like a worthy DIY project to me.
 
Sig: I don't know what the composition of ceramic is. Some unglazed ceramic is acceptable to cook food in. I've had ceramic bathroom tiles in my tank under clams and they seemed to be benign. The porous bricks used for some nitrate reduction filters are either glass or ceramic.

The topic is boiling/sanitizing rock to get maximal phosphate reduction and eliminate undesirable plants/animals from rock. Mojoreef has a very nice SPS reef, and older reef than most, and he is sanitizing his rock in a BB setup. IF the only thing the rock is good for is a filter, and the only filtration is driven by bacterial action, why wouldn't you boil rock or use some type of synthetic rock? It is the logical conclusion of the BB argument.
 
Howard: I agree thats why I boiled mine. I figured if I wait for 6-9 months for the cooking process to complete, then I might as well boil out all that algae and cook it later for the bacteria to consume the phosphate. Should be a lot quicker even if it cycles.

I'll look around for companies making ceramic vases and see what I can come with. Only problem is how to make it porous enough so that it can accomodate the denitrifying bacteria.
 
it seems to me that boiling the rock or starting with base rock, and then seeding it with live rock, would be the best bet. This is similar to seeding the sand bed with a handfull of sand from one or more established systems.

The questions are:
1) whether boiling actually removes phosphates and/or detrital remains of anything else that was killed in the boiling process

2) whether it is faster or more preferable to cook live rock or seed base/boiled rock (assuming strict adherence to each procedure to ensure success).

3) If you seed the rock, should you do this in the tank or while cooking?

for the first question, anecdotal evidence has been provided that it does and does not remove phosphates/nutrients from the rock. i call this undecided until i see data.

as for the second question, it seems to me that the strengths of cooking live rock are a more plentiful and varied bacterial population, as well as faster coralline recovery and survival of small crustaceans. downsides are the work and time involved. the strengths of seeding base/boiled rock are that you are starting with a very clean system and allowing the bacteria to grow INTO the bioload, rather than starve, die off, feed more, starve, die, repeat cycle, until equilibrium is reached. It may also be cheaper. Downsides include little or no coralline and little diversity in bacterial or other lifeforms (which some still consider a plus).

regarding the third question, if there is not enough food for bacteria to spread to the base rock (as in the low-nutrient cooking environment), then cooking will merely clean up the rock you are seeding with, but base rock will not become "live" rock until you put it in the tank and give the bacteria something to eat. I think that the die-off that will occur in the live rock while cooking should provide enough food for the bacteria to populate the base rock, but this is mere speculation.

here's a question of my own: if you cook live rock forever, i.e. keep swishing and maintaining nutrient-free water, will all the bacteria eventually starve and eat itself until there is nothing left, and you are back to nothing but base rock again? it seems probable if you take the theory behind rock cooking to its logical conclusion. we simply stop the process before this, after the rocks stop shedding, which is intended to be the point at which all the bound phosphates in the rock are used up.

interestingly, if you add fish or corals at this point, then you are again letting the bacterial population grow INTO the bioload of the tank, rather than die off and cycle repeatedly, which seems to be the old way to set up reef tanks.

PLEASE post any thoughts on this! i know a lot of these aren't new ideas, i'm just trying to tie a bunch of them together...
 
Esper:

If your starting, yes base rock would be best. Just seed with live rock.

In answering your questions: My opinions are:

1) I dont think that the phosphate will be removed by boiling. Its denitrifying bacterial action that does that. I boiled mine to rid of those pesky algae (endemic?) I described above and hopefully to hasten the removal of the existing detritus in my rock so that the new bacteria will have to go deeper in the rock and absorb the phosphate.

BTW after boiling I used a compressor to blow air into the rock.

2) IMO it should be quicker. I also selected three rocks that had the best coraline growth (dont care about other stuff, cant see them) to eventually seed the boiled rock after the readings are zero. They are in my quarantine tank. The copepods I will get from my friends refugium.

3) I think you should seed the base rock with live rock during cooking and not in the tank. You would'nt want to be surprised at the amount of sheding those base rocks might do once they become live :eek1:

The die off in the boiling will provide plenty of food for the bacteria and I dont think this is speculative if you believe in the nitrogen cycle. I will just have to do regular WC and swishing while cooking the already boiled rock. The reason is so that bacteria wont have anything to feed on the water column and get the nutrients from the rock. Which is want we want.

YMMV, I am doing this to start a new clean system once and for all and I dont intend to hurry this up. What I intend to do now is just research to improve my husbandry skills.

FWIW, after boiling the rocks/blowing and putting them back in new water, they became cloudy, just like a cycle in a tank. It disappeared after a two days. Then the water turned to a greenish color after that, in which case I did a water change with the swishing. The rocks smelled a little, but nothing compared to the smell they emitted when I cured them over two years ago. It looked like brand new live rock to me.

As for the forever part, there will always be bacteria, its everywhere, though if there is less food, there will less of them also. Of course if all the phosphates are totally removed (theoretically, cant see how this happens), then I dont think there will be any cuz its limiting as per redfield ratio. C=106,N=16,P=1
 
wow, thanks for the complete response! i think most of my confusion was due to my ignorance of how bacteria uptakes phosphate. you are right about how bacteria covers everything, i had forgotten about that...
 
Bacteria stores P.

Boiling kills bacteria.

P is released.

Wash rocks a lot after boiling. Faster than starving your rock for 6 months..but will kill just about everything.

'Shedding' as many observe during curing=bacteria population crashing and dying.

Yes this removes phosphate bound by bacteria.

Gradually, over time bacteria can bind phosphate again, even after extended curing periods has 'purged' the rock once the bacteria are fed (fish poop, excess food, etc.)

Key is to balance export vs import of nutrients. 'cooking' rocks does not fix this.
 
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