[peachykeen]

what would be the ideal sandbed for a 65 gal, reef tank (fish and corals). is 2 inches ok, or would it be better to go more, been a little hesitant to add more because of the latest algae problem, but would perfer to do what best overall for tank and not not best for me

[sihaya]

Originally Posted by peachykeen

what would be the ideal sandbed for a 65 gal, reef tank (fish and corals). is 2 inches ok, or would it be better to go more, been a little hesitant to add more because of the latest algae problem, but would perfer to do what best overall for tank and not not best for me

Go with 3-4 inches of masonry sand (the cheap silica sand from the hardware store is just fine). Sandbeds by themselves do not contribute to algae problems so I don't know where the heck you're getting that from. If anything, a properly set up and maintained sand bed will help with algae.

[smidoid]

Originally Posted by sihaya

Go with 3-4 inches of masonry sand (the cheap silica sand from the hardware store is just fine). Sandbeds by themselves do not contribute to algae problems so I don't know where the heck you're getting that from. If anything, a properly set up and maintained sand bed will help with algae.

Dr Shimek has some interesting posts on DSBs and I have to agree with Sihaya that they should not normally cause an algae problem. What you might have heard is the possibility that they can become a nutrient sink - and a possible time-bomb. Properly maintained, this should not happen, but I always defer to Dr. Shimek in this area.

I want some Oolitic sand for my bed (the sand bed that is, it would be too itchy) but no one seems to know where to get it over my way.... ? Help.

[peachykeen]

wasnt suggesting sandbed caused algae, was just wondering what the going sandbed dimensions were, setup is fine and far as maintainance i spend at least an hour of quality time with my tank daily, the only thing i can think of is to increase sand dwellers, and not with crabs to ensure good cleaning on bottom, all test are coming out fine

[smidoid]

Shimek says, IIRC, that a DSB should be at least the size of the display and several inches deep 3-4 minimum - so if it's in the display, then no problem. I think Gene (Zhenya) has one in his display - you might try to track him down.

Live rock and live sand (both expensive) can seed a DSB in a few months and you might find an LFS or a club that will let you have an innoculation.

I suspect Sihaya is right to suggest cheap sand - you might just want to top it off with a thin layer of live aragonite to kick-start it.

Dr. Shimek hangs on here now and can be contacted via www.ronshimek.com (amazingly for such a busy guy, he even answers his mail!)

[sihaya]

I know Dr. Shimek. Though he adamantly denies that I am any kind of friend to him (the miserable bugger)... he advised me himself that I could use masonry sand from a construction supply store.

[smidoid]

Neat. But (sorry to be fick) but what's masonry sand? We get all sorts of sand here, but I don't remember masonry sand. Bloody language barriers.

[The R/C Man]

Originally Posted by sihaya

Go with 3-4 inches of masonry sand (the cheap silica sand from the hardware store is just fine). Sandbeds by themselves do not contribute to algae problems so I don't know where the heck you're getting that from. If anything, a properly set up and maintained sand bed will help with algae.

Argonite sand dissovles over time assisting with things such as calcium etc, so why would you want to use a silica based sand?

[smidoid]

Originally Posted by The R/C Man

Argonite sand dissovles over time assisting with things such as calcium etc, so why would you want to use a silica based sand?

Oooh! Back of the net!

Greg's got a point there - I wonder why Dr. Shimek suggests silica?

I love a good fight at 4am!

[sihaya]

Originally Posted by The R/C Man

Argonite sand dissovles over time assisting with things such as calcium etc, so why would you want to use a silica based sand?

Um... no, it doesn't... at least not to any degree that would make any difference at all what-so-ever. And if your calcium and alkalinity ever did actually get sooo low that the dissolving of your calcium carbonate substrate started to make a difference... well, you'd have some big problems my friend (ones no sand could help you with).

Why do I like silica based sand? Because it's cheap, it comes in all sizes, and it doesn't dissolve.

[smidoid]

Originally Posted by sihaya

Um... no, it doesn't... at least not to any degree that would make any difference at all what-so-ever. And if your calcium and alkalinity ever did actually get sooo low that the dissolving of your calcium carbonate substrate started to make a difference... well, you'd have some big problems my friend (ones no sand could help you with).

Why do I like silica based sand? Because it's cheap, it comes in all sizes, and it doesn't dissolve.

She shoots - she scores - crowd goes wild!

I'm sure I read somewhere that Aragonite dissolves slowly over time - didn't someone mention half-life? Now, it could be that this is down to erosion, but then were does all the eroded material end up?

Mind you, I can see Sara's point - the normal way to dissolve aragonite in a calc reactor (IIRC) is to bubble CO2 through it to make the water slightly acidic (one of the acid rain effects in fact) and that puts some calc into solution while cancelling out the affects of the acid. If the water drifted from 8.x all the way to below 7, you've got real problems!

[sihaya]

Theoretically, glass dissolves *over time* too.

Bubbling CO2 makes the water significantly more acidic. Like you said, it's like acid rain (which dissolves statues). And like I said, if your tank water parameters are reading like acid rain, you have bigger problems!

[Ninong]

Originally Posted by smidoid

Dr Shimek has some interesting posts on DSBs...

He has also written several articles on sandbeds, some of which are actually still available online:

Sand Beds:
How Sand Beds Really Work

Feeding Begets Food, 1: or… Food Production By Design, How A Deep Sand Bed Can Produce Food For Reef Inhabitants.

What lives in live sand? (Do you really want to put your hands in this stuff?)

Odd Pods, Tanaids in Reef Aquaria
The Infamous Detritivore

I want some Oolitic sand for my bed (the sand bed that is, it would be too itchy) but no one seems to know where to get it over my way.... ? Help.

Oolitic simply describes particle shape (egg shaped). You want some aragonite sand. It should be available over there, although at a higher price than over here because all of the aragonite sand in the world comes from the same place in the Bahamas.

ESV in New York sells oolitic aragonite sand but I don't know if it's available in the U.K. Some people like this product because it is a very small particle size.

P.S. -- Ron Shimek has links to most of his articles here. Most of the links work but some do not.

[Ninong]

Originally Posted by peachykeen

wasnt suggesting sandbed caused algae, was just wondering what the going sandbed dimensions were...

The answer to your question depends on which method you choose or which expert you ask.

If you ask Dr. Ron Shimek, he will tell you to go with a fine particle size and a minimum depth of 4" (10 cm). Read his sand bed articles that I linked above for details.

This doesn't mean that other approaches won't work. You will have to decide for yourself, after researching the topic, which approach you want to try. I have a DSB (deep sand bed) of fine particle aragonite sand that is approximately 6" deep. This approach has one distinct disadvantage: It is almost impossible to run VERY high water movement. People who are will to compromise when it comes to really high water current will not find this to be a handicap. People who wish to try very high water movement will be disappointed. I have learned to live with it the way it is and not attempt to go too crazy with water movement.

[Ninong]

Originally Posted by smidoid

Shimek says, IIRC, that a DSB should be at least the size of the display and several inches deep 3-4 minimum

Ron recommends a minimum depth of 4". He's also a stickler for the minimum mass of the sand bed. In other words, Ron does not recommend DSBs for a 20-gal tank because the mass would be too small. Something around 40 gallons is probably a safe minimum for Ron's sort of DSB.

Live rock and live sand (both expensive) can seed a DSB in a few months and you might find an LFS or a club that will let you have an innoculation.

True live sand can seed a DSB but live rock cannot because the animals that inhabit live rock are not the same as the animals that inhabit sand beds. Nitrifying and denitrifying bacteria can migrate from live rock to the sand bed but not many animals will.

I suspect Sihaya is right to suggest cheap sand - you might just want to top it off with a thin layer of live aragonite to kick-start it.

Ron Shimek's approach is based on the particle size of the sand, not whether it is silica sand or aragonite sand. That's his approach.

Personally, I prefer aragonite sand. For one thing, it looks nicer.

[Ninong]

Originally Posted by smidoid

Neat. But (sorry to be fick) but what's masonry sand? We get all sorts of sand here, but I don't remember masonry sand. Bloody language barriers.

Masonry sand is simply quartz (SiO2) sand. Aragonite is calcium carbonate (CaCO3) sand. Quartz sand is terrestrial sand and is tan or beige in color. Aragonite sand is a marine product and is white in color. The aragonite sand that comes from Marcona Ocean Industries in the Bahamas was formed by precipation. It is sold under brand names such as Carib-Sea in the hobby or under brand names such as Oldcastle in home improvement stores (garden department).

Aragonite sand is also found on tropical beaches around the world. This sand is composed of remains of Halimeda and other calcareous algae, foraminiferans, echinoderms, coral skeletons that have been reduced to fine particles by the action of parrotfish, etc.

[Ninong]

Originally Posted by smidoid

I'm sure I read somewhere that Aragonite dissolves slowly over time...

There are three different crystalline forms of calcium carbonate: Aragonite, calcite and another one (look it up for yourself, I forgot). Calcite is a much more stable form than aragonite. In other words, calcite doesn't dissolve nearly as easily as aragonite. Aragonite will dissolve, but only when the pH drops to 7.6 or less. That's the basis of calcium reactors -- aragonite media subjected to lowered pH by the injection of carbon dioxide.

Experts disagree on the amount of dissolution of aragonite sand in marine aquaria and whether it is enough to provide significant benefits. This is a controversial subject. For further details, do your own research. Ron Shimek is convinced that it does not provide significant benefits. According to Ron, even if a small quantity of aragonite dissolves in microenvironments where the pH falls below 7.6, it is almost immediately reprecipitated. However, before we get too far into this, just remember that one well known figure, Professeur Jaubert, has based his entire method on the supposed benefits to be had from the dissolution of aragonite sand (actually aragonite gravel). (P.S. -- Only the French version of that website is complete. The English and Italian versions are 'under construction.')

This is another one of those topics where you will have to make up your own mind after researching the topic.

[smidoid]

Thanks (again!) Ninong, that's really helped clear up a few things for me.

I've gotten Aragonite here, yes, it's preeeeety expensive. The live mix that they sell here (bacteria only I guess) is £23 (around $38?) for a bag of, well, wet sand and bugs! I don't know how that compares to you. I have to agree that it's quite beautiful in the display - although I'm only using a light sprinkling.

I was after oolitic - sugar grain or smaller - aragonite but I'm beginning to wonder if you can even get it! The stuff I have is sugar grain but feels a little sharp - now if only I had a microscope! Failing that, a some type of light clay would do (I'm heading down the miracle mud way - but I don't see the point of paying a fortune for MUD!!)

Since this is going in my (rather pathetic) refugium - it doesn't matter a pair of fetid dingo's kidneys what it looks like. However, I don't want to screw up the water chemistry, turn the water brown or worse, poison the fish!

OK - so am I safe in putting "soft" building sand in there? I don't know what goes into it it - so how do we know it's safe? After my latest screw up, I don't really want another disaster or it's my ghoolies!

[smidoid]

Originally Posted by Ninong

There are three different crystalline forms of calcium carbonate: Aragonite, calcite and another one (look it up for yourself, I forgot). Calcite is a much more stable form than aragonite.

I'm not even going there!

Wikipedia has this: http://en.wikipedia.org/wiki/Calcium_carbonate

I'm going to guess with Travertine (as I'm pretty sure chalk isn't crystaline). Damn, I should have paid more attention in geology!:slap:

Well, I supose I am learning something (slowing, but it's sinking in!): last fall I hadn't even heard of Aragonite.

As always, I value your input. Honestly.

[The R/C Man]

Originally Posted by sihaya

Um... no, it doesn't... at least not to any degree that would make any difference at all what-so-ever. And if your calcium and alkalinity ever did actually get sooo low that the dissolving of your calcium carbonate substrate started to make a difference... well, you'd have some big problems my friend (ones no sand could help you with).

Why do I like silica based sand? Because it's cheap, it comes in all sizes, and it doesn't dissolve.

If you have read any books like Anthony Calfo's Coral Propagation for example he specifically states that disolving sand specifically benifits the over all calcium levels in the tank. He even mentions that some people have successfully run their tanks with especially deep beds of better than 6" and do not add calcium. Also the calcium based sand (natural) that obviously dissolves over time (as proven by some photos of my tank) must go somewhere. Ultimatley it is used by the corals for growth.