ROWA phos questions

[Hooked]

I had posted in another thread that I was successfully keeping bryopsis in check by maintaining high levels of alk (14-16 dkH) and magnesium (1400-1500). It was suggested to me that this might not be a good idea in the long run and I should try to determined the cause of the problem.

Okay, so I checked for phosphates and nitrates and have zero nitrates and maybe a trace of phosphates in the water column. I say maybe, because the color of the sample barely changes. I checked my ro/di water which has a tds of zero and got the same result.

I also took a sample from the sand bed, which is only 8 months old, and from an area with bryopsis and got readings of less than 0.2 ppm (Red Sea test kit). The latest RH-F article about reef chemisrty suggests levels below 0.03 ppm are acceptable--my test kit isn't that precise.

Now, to the ROWA phos questions. I am using ROWA phos. I currently have 250 ml in a Magnum 350 that is six weeks old. I put it in the bag that was provided then inserted it into the media canister. I didn't like the way it fit in there--I wonder if I can place it loose in the media canister?? And how long should I expect it to last??? And last, is the Magnum 350 okay for this purpose???

Any input is greatly appreciated TIA

 

[DonW]

Rowa should be fluidized, in order to take full advantage of the surface area. I would think a Magnum would work fine. Its pretty small stuff and you dont want it to get out. I would see if the screen is tight enough.
I would also slow the flow. Run it just to the point that it fluidizes the media.

Don

 

[mojoreef]

Katrina are you getting the same P reading in the water column as you are in the dsb and algae areas??


Mike

 

[Hooked]

Mike, it is higher in the dsb and algae areas.

 

[Hooked]

Don, when you say fluidized, do you mean it should be suspended in the water and moving? If so, then in needs to be "loose" in the canister, right?

 

[DonW]

Don, when you say fluidized, do you mean it should be suspended in the water and moving? If so, then in needs to be "loose" in the canister, right?

Yes, I just can't remember if your carbon cartridge is fine enough for Rowa. I gave my Mag-350 away.

Don

 

[tamarindthai]

[
Don, when you say fluidized, do you mean

place a ROWA bag in fluval404,,that shoul it be good enough?
dang

 

[mojoreef]

Katrina they way it works is that water that apsses through it that has Inorganic P will have the P absorbed from it. The reason fluidizing it is much better with rowaphos and simular is that because it is so fine in grain size that it tends to pack up and just allow tunnels to drive the water through, so not very effective. Fluidising the media allows all surfaces of the media to work at the absorbtion process. I will post a link to a cheap and easy filter below.
On to your problem. On the LR, detritus will be shed from it as a natural process through the action of bacteria, most of that is in particulate form. the best meathod for dealing with it is to direct flow towards it to blow it off, if you cant get that kind of flow then blow it off manually with a turkey baster. If it is allowed to stay on the rock it will soon be utilised by algae of some kind on the top sides.
On the DSB. The actual sand particles of the sand come fully loaded with bound up Inorganic P before it even gets out of the bag and into your tank. This is ok though as it is bound up in the matrix of the particle. As a dsb matures it begins to develop the defferent zones (ie areobic, anaerobic and sometimes anoxic)In the areobic zones thier is a little chance of the Inorganic P being released by the action of bacteria but most of the time thier is so muc food in thier they do not need to expend the energy. In the anaerobic zone where oxygen begins to deplete and through the enzynes of bacteria these sand particle begin to melt. Most DSB folks promote this action as buffering the tank, and it does as the calcium carbonate is released (same concept as in your calcium reactor) The problem with this action is that the Calcium carbonate is not the only thing that is release throught the action of the ph and bacteria. The Inorganic P is once again let free. It usually follows the same pathways as does the other nitrogen compounds in the bed. What ends up happening is that the IP is made available to the critters that live in the higher zone of the bed. Now these critters have bothe this form of IP and the normal flood of IP that comes from feeding/detritus and waste, Usually it is more then can be handled by the infuana, the result is the leeching of IP into the tank water and thus making available to a whole new world of critters and algal life forms. Thats where you are at right now. What you need to do is to give your Rock and sand a bit of a break and help it export some of the nutrients that it is experencing. Blowing or sucking off the detritus on the rocks will help with that. In the sand you should try to manually syphon off some of the over load that is compiling in the bed. This can be done by lightly stiring the top layer of the sand bed (about 1 inch down max) and at the same time with a syphon suck what ever matter that is released by that action. What you are doing is removing a large ammount of the nutrient load that would have had to be processed or bound up by the Organics in the bed, this should allow them a better chance at catching up with the task ahead of them. Make sure when doing this that you keep an eyeout for dark colored or black areas, if you see them you are to deep, so stop and move further up the bed.

http://www.aquaticeco.com/index.cfm/fuseaction/product.detail/iid/7843


hope it helps


Mike

 

[Hooked]

Thanks Mike, that was a great explanation. I've been blasting the rocks, but I'll start doing it more often (and more thoroughly)and plan on a sand bed cleaning this weekend.

Thanks for the link. I was trying to figure out if I could make one similar to the TLF model, but I like that model even better.

Thanks

 

[mojoreef]

Katrina that unit is a pretty simple one but its good enought to do the trick if you have room for it.

glad it helped

Mike