carbon and rowas during cycling

[williammuk]

In any case, you have nothing to lose by putting the rowa on day 1. If there is nothing to absorb, the rowa can be used forever.....

That's what I'm hoping also.

[BFG]

When do we need to introduce or use carbon? Do we need to leave it running for a day, week or month? How do we know that the carbon absorption has maxed out and need to be replaced?

[kareen]

ok ok.....but how PO4 got absorbed by the sandbed? 

Care to show some links...... Thank you very much in advance.

**SRC is a good place to get all sorts of information.... I admit I have never, ever think of putting rowaphos during cycling stage**

[diabolus]

this is from Advanced Aquarist -

Likewise, phosphate can precipitate onto the surface of calcium carbonate, such as onto live rock and sand.  The absorption of phosphate from seawater onto aragonite is pH dependent, with the maximum binding taking place around pH 8.4 and with less binding at lower and higher pH values.  If the calcium carbonate crystal is static (not growing), then this process is reversible, and the aragonite can act as a reservoir for phosphate.  This reservoir can make it difficult to completely remove excess phosphate from a tank that has experienced very high phosphate levels, and may permit algae to continue to thrive despite cutting off all external phosphate sources.  In such cases, removal of the substrate may even be required. 

[scarab]

diabolus. Interesting article.

[bloodlamb]

hi,

Just to add I saw this article in FAMA Sand Mail column saying that the phosphate binded in LR and coral sand cannot normally be released back into the system because of the low pH required for resolution. However if a bio-flim forms over the surface, it could extract out the phosphate binded in it.

[Ancelot]

Phosphate and carbon question: A once fought over topic

Here's my opinion:

I agree that the generation of phos during cycling is inevitable. Therefore i agree that using phosphate is necessary to control the possiblity of having PO4 rooting on your LRs and your DSB (tats if you have one ) So nothing wrong in that..certainly something we should pick up.

Here to clear a misconception (Hope i clear it, seniors correct me if i am wrong):

However, I hope everyone notices that i didnt say PO4 being the cause of cyano in your tank esp on your DSB. and because of cyano indirectly let us to think that it is caused by high levels of silicate and phosphate. Well, things are not so simple as it is. High organic nutrients are the fuels of cyano other than dissolved PO4 and silicate eh? (correct me if i am wrong). Therefore, when considering cyano we should open ourselves to a bigger picture and not kill the bird too quickly with a stone. I also hope to let everyone know that cyanobacteria are actually important bacteria that helps in the fixation of nitrogen. So when you have DSB or live rocks, you have them inside whether you like it or not. But whether more or less cyanobacteria depends on how you control their numbers. Good protein skimming is a good solution to remove them and also controlling your high organic nutrients. Also, having a good waterflow in your tank helps to send suspended mucus and detrius to the exit chamber (overflow) and prevent them from settling down to collect bacteria and end up as cyano.

Therefore, i wonder how many people when reefing asked yourselves this question before complaining abt cyano, "Why did cyano just grow on some areas of my tank and not everywhere initially?" I hope everyone sit down and think over this question. The answer and solution are actually not far away.

Just my 2 cents worth..

Seniors, feel free to correct me.. i hope to hear honest and constructive comments and not out of ego kind of comments. thanks

[Ancelot]

Now here's a bit about DSB:

I think after reading those comments abt DSB, the idea of having a 2-3inch sandbed is kinda completely washed out on everyone's mind. However, I still prefer to stand by the side of DSB. Afterall, DSB is started by somebody who spent years researching on it and BB certainly looks very unclassical (sorry that i have to say that)

I hope to let everyone know that DSB is not an elixir that will prolong your tank's life just by utilising it. The reason that DSB is good only if you are capable of doing maintence on it like introducing sand sifters on it or do maximum gravel washing. Gravel washing helps to stir the sands to relieve the bioload your bacteria is suffering from and trapped nitrogen gas, so prolonging your DSB. But if you are not going to do any of that, then whats more left is nothing but a pile of unspeakable sand and dying bacteria.

Adding to something,

Can water changes remove PO4? yes! why not?! So start changing some now lor..

Just my 2 cents worth..