Does Siporax leach Silica?

[jason2459]

..., and can you please tell me what are you doing to remove the Si you had/have?

I suggest sponges [emoji4]

 

[Gary Wilkinson]

So it is as I suspected. Thanks for that.

Do you know if it will continue to leach Si, and can you please tell me what are you doing to remove the Si you had/have?

I have found GFO binds Silicates, my levels are now down

having learnt a lesson, the second batch of Siporax was washed in water change water
this removed most of the silicates, the spike was much less only 201 ug/L close to NSW top end, though I would like it lower, as I do has some nuisance spunges

I think it's the dust rather than the media itself as it falls after the initial spike, if you use GFO

 

[Fragzilla]

I have found GFO binds Silicates, my levels are now down

having learnt a lesson, the second batch of Siporax was washed in water change water
this removed most of the silicates, the spike was much less only 201 ug/L close to NSW top end, though I would like it lower, as I do has some nuisance spunges

I think it's the dust rather than the media itself as it falls after the initial spike, if you use GFO

Makes sense. If I move the siporax or jig it to clean the media I see more diatoms appearing.

I think I'm going to empty the tank, remove the siporax, add some rock rubble and let it settle out.

 

[Fragzilla]

Thanks for all the help and information guys, your support is brilliant

 

[Gary Wilkinson]

Makes sense. If I move the siporax or jig it to clean the media I see more diatoms appearing.

I think I'm going to empty the tank, remove the siporax, add some rock rubble and let it settle out.

I would leave it alone and let it do its work, rubble does little more than form a home for PODs

 

[Randy Holmes-Farley]

So it is as I suspected. Thanks for that.

Do you know if it will continue to leach Si, and can you please tell me what are you doing to remove the Si you had/have?

FWIW, the only things to reduce it are phosphate binders such as GFO, water changes with lower levels salt water, or allowing it to be consumed by organisms such as diatom, sponges, snails, etc.

It may slow as the surface of the siporax changes (dissolving some of the surface and binding other stuff to it), but I've not seen any data testing that in a reef tank.

 

[Fragzilla]

FWIW, the only things to reduce it are phosphate binders such as GFO, water changes with lower levels salt water, or allowing it to be consumed by organisms such as diatom, sponges, snails, etc.

It may slow as the surface of the siporax changes (dissolving some of the surface and binding other stuff to it), but I've not seen any data testing that in a reef tank.

But if diatoms or sponges consume the silica it's still in the tank isn't it? Or is it feasible to think the diatoms could be skimmed out? If the sponges grew then couldn't continue to support themselves I assume they will eventually put whatever they're made out of (silica & carbon?) back into the water column. Or would one harvest the sponge much like macro algae?

Where I have the bag of siporax in the sump it is exposed to light. The siporax looks brown/orange in places. Not sure if that's localised diatoms but it sure looks like it.

I think that because I'm using the tank for zoas and that zoas seem to suffer from diatoms (grow between polyps on stalks) that I will be better placed to eventually remove it. it does a good job reducing nitrates to zero though, I'll give it that.

Randy. Out of interest and possibly as a prequel to another problem / issue / question I have, is there a level of Si that becomes toxic in a reef tank, and if so what would be the observed impact on hard corals?

Also can Si become bound into live rock?

 

[Randy Holmes-Farley]

Diatoms and sponges deposit the silicate they take in and make silica. While it is possible some may redissolve if they die, I don't think that is any real concern. It would be slow and other organisms will take it up.

Here's how fast it dropped in my tank:

Feature Article: Silica In Reef Aquariums ? Advanced Aquarist | Aquarist Magazine and Blog
http://advancedaquarist.com/issues/jan2003/feature.htm

from it:

Figure 4. The concentration of soluble silica as a function of time after dosing. Dosing was done at t=0. The concentration for t=0 (30 mM) is an estimate based on what was added and the estimated total system volume.

 

[Fragzilla]

I would leave it alone and let it do its work, rubble does little more than form a home for PODs

Thanks mate, your probably right but I just don't trust it now and ideally I would like to not have to rely on phosphate remover long term so I can go back to a bacterial driven nutrient management programme.

 

[Randy Holmes-Farley]

duplicate answer