Silica versus Aragonite

[davelin315]

OK, I think this covers the basics. If you want to explain your answers please do. Answer number 1 and then answer either 2 or 3, not both. If you have had both kinds, answer the poll for each experience you have had.

 

OK moderators, I can't modify the post. Can you add a choice for questions 2 and 3 of does not apply?

[flowerseller]

It won't let me vote for arragonite and that I'm happy with it.

[davelin315]

I stuck something in there to ask a moderator to add a poll response so that you can vote for all three. I guess you have to have something down for each question and can't leave something blank?

[dandy7200]

Mixed, usage here I have agronite in the display and silica in the lerge refugia.

[mogurnda]

I use silica, and it has been fine. Aragonite might be better for buffering for low Ca demands, but if you have growing stony corals then you will still need to supplement Ca and carbonate. Calcareous sand would probably look a little nicer.

 

No issues with diatoms. I had a hydrologist laugh hysterically at me when I suggested that significant amounts of silica could dissolve from playsand.

[YBeNormal]

I'v read lots of threads and articles on the pros and cons of silica sand in a reef tank and while I'm not convinced that it is as bad as some might think it is, I do feel that aragonite is a better choice and worth a few extra bucks.

 

I have aragonite in a small 29g reef, a thin layer of crushed coral in an attached 75g puffer tank (soon to be replaced with aragonite), aragonite in my sump and White Castle silica-based sand in a 5g HD bucket RDSB topped with a thin layer of CC. Of the three types of substrate, CC has to be my least favorite, followed closely by silica sand. The CC and silica sand will soon be history in my tanks. JMHO....

[xCGx]

I used mixed in my main display and only silica play sand in my RDSB. I didn't see a change from when the main display was aragonite only to being mixed.

[Ne0eN]

I use Argonite based Southdown sand mized with CaribSea Aragonite product simply because that's what beeing used in the ocean.

 

-- Rob

[scarletknight06]

I used silica b/c I couldnt find anything aragonite based that had the fine grain size that I like. Havent noticed a down side yet, but its only been in there for 2 months. I've read the only downside is the occasional diatom outbreak, but my theory is that a good clean up crew and overskimming, make that a non issue.

 

People always say that aragonite based substrate has a buffering ability for calcium and alkalinity demands of corals and this is just not true. IME, in a freshwater tank it will keep your pH higher. But in a saltwater tank your pH would have to be below 7.0 for it to provide any calcium or dkh for your corals.

[rsaavedra]

Aragonite! Happy!

[GaryL]

i used yardright when it was available and have been happy. i have had sandstorms but it corrects itself. i think the greatest advantage is the surface area of the grains.

[flowerseller]

People always say that aragonite based substrate has a buffering ability for calcium and alkalinity demands of corals and this is just not true. IME, in a freshwater tank it will keep your pH higher. But in a saltwater tank your pH would have to be below 7.0 for it to provide any calcium or dkh for your corals.

Next time you're bored and want to do a little science experiment, gently work your PH probe down into your sand as far as you can. Oh, you don't use arrangonite, sorry

[davelin315]

Next time you're bored and want to do a little science experiment, gently work your PH probe down into your sand as far as you can. Oh, you don't use arrangonite, sorry

 

Anyone have two sets of pH probes that would like to try this out? Set up a dual sand bed in the same aquarium, one half silica and one half aragonite, divided in half and kept completely separate to see what the results are? I'd run it in school but I have only one pH pen that was donated and I don't think it is working very well anyway (the probe had dried out when I took it out of summer storage and I've been trying to nurse it back to health - the readings don't jump around as much anymore, but I'm not sure if it's fixed or not).

 

Hmmm, maybe I will do it anyway at school in a 10 gallon tank. How deep do you think I'd need to make the sand bed to do this? Also, since the probe is fragile, should I take a piece of pvc and sink it into the sand and keep it hollow so I don't damage the probe? Or, should I use a syringe to pull water out from the bottom of the sand bed?

[F&Fmgr]

Anyone have two sets of pH probes that would like to try this out? Set up a dual sand bed in the same aquarium, one half silica and one half aragonite, divided in half and kept completely separate to see what the results are? I'd run it in school but I have only one pH pen that was donated and I don't think it is working very well anyway (the probe had dried out when I took it out of summer storage and I've been trying to nurse it back to health - the readings don't jump around as much anymore, but I'm not sure if it's fixed or not).

 

Hmmm, maybe I will do it anyway at school in a 10 gallon tank. How deep do you think I'd need to make the sand bed to do this? Also, since the probe is fragile, should I take a piece of pvc and sink it into the sand and keep it hollow so I don't damage the probe? Or, should I use a syringe to pull water out from the bottom of the sand bed?

 

 

i would try the latter...

 

chip, have you done that before and have you got high (er) alk and ph readings? I thought that you need acid accumulation to disintegrate the media (which is found in FW). Do you think that there is sufficent acid accum. and/or production to do this in a SW tank? Id be very curious to see the different chemical reactions that might occur in a aragonite DSB.

 

Thanks

 

Sean

[Lee Stearns]

Interesting proposition- I had always believed the buffering effect of aragonite and was not terribly worried about silicate feeding diatoms. It would argue for a deep sand bed or at least one greater than 3 inches because the lower layer would not get the circulation and may go anaerobic- Whether this anaerobic N2 bubble creating area would have a lower ph and cause some release of calcium and alk form the aragonite would be an interesting question to ask Randy over on RC- Not sure what the PH of the N2 bubbles are or what the anaerobic area conditions would be that could break down nitrates to N2 gas bubbles. I will check when I get my PH meter back- I have two but one is in the calcium reactor and one is loaned

[mogurnda]

It took me less than 24 hours to remember I have a second tank with a 6" aragonite sandbed, a relatively low Ca demand, and I still need to dose kalk and vinegar. I'm sure the aragonite helps a tiny amount, but not a whole lot.

 

Do people using more than one method get more than one vote?

[scarletknight06]

well if you don't want to believe me, just ask Randy Holmes Farley on RC.

[davelin315]

Vote as many times as you have set ups. As far as not believing you, that's not the case. I've read things on both sides from people who are very experienced and knowledgeable, including Randy, about the benefits. I think you can find support for whichever side you fall on. With that in mind, I'm thinking of taking a tank, dividing it in the middle with a sheet of acrylic probably about 8-10" high, filling one side with silica sand and the other with aragonite. Run this tank with some seedings from a silica bed for the silica side and an aragonite bed for the aragonite side for a couple of months without anything else other than the sand and a few burrowing snails and see what the results are. I figure that the water column itself will not be affected but the sand at the very bottom of the tank will be where the water could show a difference. I don't know if I can run this experiment with the kids at school or not, or even when I can start it, but that's what I'm thinking. A variation on this would be to install a couple of bulkheads on the bottom of a tank, fill it up the same way, and have a drain in the bottom of the bulkhead that could let water out of the bottom for testing. That way I could draw samples without disturbing any of the sandbed itself. Anyone want to help me with this? I figure I could use something like a 10 gallon tank if someone has the drilling skills.

 

Dave