Does Siporax leach Silica?

[Fragzilla]

Hello,

I've been trying to beat a constantly cycling diatom bloom in my frag tank.

The tanks been setup for about 5 months now and I'm still getting these blooms.

I was speaking to friend who owns a aquarium supply website and he suggested that it may be the siporax leaching silica into the water that is causing the diatoms to continue to grow.

Is this possible?

I've been blaming my RO water, but I change the DI when it reads 1 on the TDS meter.

I have refugium with chaeto (eventually gets covered in diatoms), live rock, skimmer and 1l of Sera Siporax Professional. 10mm deep coral gravel bed.

I'm so frustrated, my zoas hate these diatoms. They grow between the polyps and on the stalks, also growing on sandbed and seems to manage well in high flow.

I'm looking desperately for a cause / solution.

 

[jason2459]

Fwiw, my silica increases before my color changing di is fully changed colors and the outout is still 0. Most TDS readers do not have very high resolutuon.

 

[jason2459]

Also, at 5 months your tank is very new and highly susceptible to diatom blooms. That is common. Food is a good source of food for them as well.

 

[Randy Holmes-Farley]

Any silica material (including sand) can release a small amount of silica/silicate as it very slowly dissolves. Higher surface area will speed the process.

But that said, the primary source may not be the Siporax.

 

[Kungpaoshizi]

It's one reason I stopped using the Seachem Matrix. Just continual blooms... (ceramics often contain silicates)
Also on the DI resin note, di resin will release silicates before it's exhausted, like Jason says above.
The trick is to add a silica anion resin(I've only found it at RO guys site; you can see it in the spectrapure filter too, the white stuff) after your RO membrane, then 2 di chambers after it with a TDS sensor inbetween the di cartridges.
Then when you see the 0 change to 1, you change the di resin, but the majority of the silicates are gone by reaching the end of the 1st di cartridge.

 

[jason2459]

My sponges like it.

 

[Randy Holmes-Farley]

Mine too. I dosed it for many years.

 

[Big E]

Siporax is sintered glass

 

[Wesus]

I had similar problem and in my case RO membrane was bad. My TDS after DI was 0 ppm and like you I replaced every time it went to 1ppm. I've replaced membrane couple days ago and refilled top off container with fresh water and looks like diatoms are almost gone

 

[new2mac]

AFAIK siporax = glass, couldn't leach silicates, at least not at that high rate to become a source for diatom bloom. Look somewhere else. Sand? Rocks? I had similar problem years ago, it appeared to be the sand, which was no name brand given by LFS. Replaced sand w/Red Sea live sand - problem gone. Not saying you have the same problem just something to consider.

 

[Randy Holmes-Farley]

AFAIK siporax = glass, couldn't leach silicates, at least not at that high rate to become a source for diatom bloom. Look somewhere else.

I'm not claiming it is the source here, but why do you say it can't be? It is able to dissolve, and higher surface area materials (such as sand and siporax) will likely release much more than aquarium side panes.

I discuss the solubility of glass and quartz here:

Feature Article: Silica In Reef Aquariums ? Advanced Aquarist | Aquarist Magazine and Blog
http://www.advancedaquarist.com/2003/1/aafeature1

 

[Gary Wilkinson]

My ICP showed a spike in Silicates after adding Siporax

 

[Randy Holmes-Farley]

My ICP showed a spike in Silicates after adding Siporax

Interesting. Thanks for the info.

 

[jason2459]

My ICP showed a spike in Silicates after adding Siporax

How much of a spike? What were previous results compared to after you added siporax? What is the source water and if using rodi do you know how long the DI stage had been in use?

 

[Gary Wilkinson]

How much of a spike? What were previous results compared to after you added siporax? What is the source water and if using rodi do you know how long the DI stage had been in use?

good questions (-)

Before adding 15 Ltrs of Siporax the last ICP was 55.93 ug/L after adding Siporax 578.9 ug/L
Triton set point for reference is 100 ( I did not rinse the Siporax a mistake)

I use RO -DI water
My incoming TDS is 70 to 84 depending on the time of year
Post membrane TDS 1
Post Di-Resin 0 if I get a reading post Di its changed
I tested my RO with ICP-OES recently and the only reading was for Si @ 0.26 ug/L

 

[jason2459]

And the other question is on how exhausted the DI was. My DI fresh removes all Si. Over halfway used up it will start leaching/passing more and more Si.

At near exhaustion but TDS still reading "0" I've had Si show up at just over 1000ug/l

 

[Gary Wilkinson]

And the other question is on how exhausted the DI was. My DI fresh removes all Si. Over halfway used up it will start leaching/passing more and more Si.

At near exhaustion but TDS still reading "0" I've had Si show up at just over 1000ug/l

resin is 2 months old I get up to a year, fortunately my tap water is very soft with little silicate

 

[jason2459]

resin is 2 months old I get up to a year, fortunately my tap water is very soft with little silicate

Very nice to last a year. Must not use a lot? I go through replacing DI, when not testing all the time, about every 1 to 2 months. I do have hardwater, probably lots of co2, but have a softener pre-filter.

 

[Gary Wilkinson]

Very nice to last a year. Must not use a lot? I go through replacing DI, when not testing all the time, about every 1 to 2 months. I do have hardwater, probably lots of co2, but have a softener pre-filter.

the joy of low TDS water the Membrane mops most things o its own,
some LFS don't even use Di Resin,
One has only Resin as his TDS is 32 from the mains, its cheaper to use resin than pay for the extra water making RO LOL

 

[Fragzilla]

My ICP showed a spike in Silicates after adding Siporax

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?