Play sand and Lava rock

[speckrb]

I tranfered my 20 gallon setup over to a 40 breeder and my fishless cycle has been done for several weeks and all is stable.
0 nitrite
0 Amonia
1.021
79°F
<5 Nitrate
8.0-8.1 PH


I have just added 2 percula clowns to my 40 breeder and they are loving life. They're PVC playground is just a riot to watch. I have 1 bag of black "live" sand as the substrate but was wondering what people thought about the aragonite play sand at the home depot or lowes. Can that safely be used in a fish only tank starting out eventualy going to a FOWLR? The large footprint of the 40 breeder is nice but it needs a lot of substrate, especially if I decide to get another yellow headed jawfish. Budget is the factor and reason for asking. There are posts where people say they used it but I could not find a topic discussion on it weighing the pros and cons and downfalls of it. If anyone knows of a resource or post of this let me know please. I am most curious if it creates enough buffer to hold hardness and PH stable. If not I think this would make a good discussion by the experienced for the less than experienced. In the past I have always gone with crushed coral but thought that the black sand would look good with the clowns. Now I am thinking that it was not a smart move as the stocking list I have picked out are mostly lighter colored fish and they may never feel comfortable on a substrate they have no chance of blending in with. The Percula's look very nice over it though.

I also was wondering if Lava rock can be used for substrate and decoration. It's very porous obviously but I can't find any info on if it leaches anything out into the water. Thanks for any insight or input.

[melosu58]

I`ve always heard that Lava rock will leach heavy metals into your water. I`ve never used Lava rock so I cant be 100% sure but that`s what I heard. Maybe you can check it out. I definitely would not use it for a substrate.

[Sadielynn]

I echo Mel here ... Tho I have had the opertunity to find faux lava I am wondering if this would be safe for frags ?

[harmy4993]

Play sand is safe lave rock isnt...there is a debate of wether or not play sand causes extra diatom. But because its a debate and people been using it for years i decided to use it. I used play sand in a planted aquarium with no problems and am using it in my reef tank that is currently cycling

[mr_X]

people used to use southdown sand for some reason over other play sand. i think it's because of what region it is collected from, but it's the silicates in non-aragonite based sand that people feel cause issues with algae, not just diatoms.
i've also heard the lava rock/metals thing.

[speckrb]

Thanks guys or gals. 86 the lavarock and see what play sand mixed with black sand looks like. And the play sand buffers good?

[Crepe]

Play sand doesn't buffer at all. Silica is completely inert.

[krap101]

I've used something like Southdown sand in my brichardi tank, and it seemed pretty similar to the aragonite I've seen. I used it to increase pH and hardness, and it did its job pretty well. The larger pieces were more flakey than granular, but I haven't seen it or Southdown in a few years. It was under the castle brand

[harmy4993]

Originally Posted by mr_X

people used to use southdown sand for some reason over other play sand. i think it's because of what region it is collected from, but it's the silicates in non-aragonite based sand that people feel cause issues with algae, not just diatoms.
i've also heard the lava rock/metals thing.

I dont see how the silicates in play sand can cause other algae problems. From the reading i did. Its the same sand used to make the tank glass. and yes your aquairium glass leaches silicates into the water over time. So it your aquarium is doing it and not causeing algae then how is the play sand?

[mr_X]

i don't know. i'm just repeating what i've read. i've never used it.

[cmor1701d]

Where are you finding aragonite playsand? It just doesn't exist in the retail channel anymore. I recently picked up a few bags of Southdown from a reefer who's had it in his basement for years.

If it is aragonite playsand then it's the same stuff sold for aquariums.

As for silica sand, many people have used it successfully. I guess the defintive article on its use is SILICA IN REEF AQUARIUMS by RANDY HOLMES-FARLEY, Ph.D. There's also some good info in Silica SAND article by Rob Toonen

I've also heard that lava rock will leach metals.

[ccCapt]

Southdown (Old Castle) sand is aragonite sand. You CAN NOT buy it anymore. The playsand you can buy at Lowes or Home Depot is a silica based sand.

SILICA IN REEF AQUARIUMS by RANDY HOLMES-FARLEY, Ph.D.
"One of the issues that has been floating around the reef keeping hobby for a long time is the issue of whether “silica” sand actually releases soluble silica or not. It is remarkable that so many people have strong opinions on this issue, and yet so few people have ever bothered to do the easy experiment of measuring it. Many even fall for the trap of concluding that since their glass aquarium is not dissolving, then silica sand must not be either."

"In the first experiment I took 3 cups of sand, and suspended it in 3 gallons of freshly made Instant Ocean salt mix that initially contained less than 0.8 mM of silica (0.05 ppm SiO2). After 48 hours of gentle stirring with a powerhead (the water was stirring, but not the sand), the silica concentration had risen to 17 mM (1.0 ppm SiO2).

I then rinsed the same sand 5 times with 1 gallon RO/DI water (1 minute each time), discarded the contents, and then ran the same stirring experiment with 2 new gallons of Instant Ocean salt mix. In 48 hours the silica concentration had again risen, this time to 15 mM (0.92 ppm SiO2).

Then I let it sit unstirred for another 96 hours, and the concentration had risen more, to 23 mM (1.4 ppm SiO2).

In a different experiment, I took about 45 pounds of sand, and added 2 gallons of Instant Ocean salt mix. I let this mixture sit for 7 days, with once a day mixing with my hands for about 30 seconds. At then end of this test, the concentration was 90 mM (5.4 ppm SiO2).

It has been suggested that the amount of silica coming from calcerous sand might actually be as high or higher than that from silica sand. To test this hypothesis, I repeated the small-scale experiments above on a calcium carbonate sand from Home Depot (Southdown). In this case, there was some soluble silica released after the first 48 h, but only 1.6 mM (0.1 ppm SiO2), or about a factor of 10 lower than the silica sand. In a long-term test, the concentration had only risen to 5 mM (0.3 ppm SiO2) in 14 days with once a day stirring.

From these experiments, I conclude that:

1. The “silica” play sand that I purchased from Home Depot can substantially raise the dissolved silica concentration in seawater.
2. The dissolvable portion of the silica sand cannot be completely removed by several rinses with either fresh or salt water, although it may be decreased somewhat by that process.
3. Southdown calcium carbonate sand (likely aragonite) can release soluble silica, but about ten fold less than the “silica” sand.

Is it OK to use silica sand? Probably. Many people do so. I also believe that not all “silica “ sands will be the same for the reasons described above relating to processing of the sand and the nature of the mineral inclusions present. So the fact that many people successfully use some (or many) types of silica sand does not necessarily imply that all people can use any type of “silica” sand without a problem."

[speckrb]

OK then - 86 it all. I may have jumped the gun as I THOUGHT the play sand was aragonite sand in the stores that everyone is always talking about. I think the bottom line for me anyways is that it is just not worth the chance or risk. Kind people that are smarter than I have already determined it is not the best solution available. I have already spent 3 months from the stand build to the cycling and got everything perfect, or as perfect as the budget will allow, and don't want to create issues for my fish, now or in the future. If things weren't stable now I would not have added anything yet and I want to keep it that way. It's all good and I will add LR and aragonite sand or CC as I can. Tonight I will try and post a pic to show it off and update myself now that things are finally happening. Thanks to all for the information, experience, input and knowledge. Fascinating experiment Larry. Thanks

[speckrb]

I was cleaning out my HOB filter which is going to be replaced by a AquaC Remora 1200 MJ protein skimmer very soon after tank gets going more. I pulled the magdive apart and it was full of metal particles from the sand I bought which was causing the grinding sound. I researched the Nature's Ocean Bio-Active Arragonite sand, and found it had a ton of elements in it. At first I freaked because I thought there was iron in the sand which the magnets caught, but cobalt, magnesium and zinc all have magnetic properties. Question I have is this desireable in a fish tank? Normally I have used crushed coral which doesn't have any of this and it works fine. Will these metals "leach" out into the water and cause issues in a FOWLR tank? Eventually I may try some zoa's or very easy hearty corals. I do not have any metals test kits yet. Any thoughts? If anyone has any bad experiences with this, I'll start replacing the sand with crushed coral. I researched a couple other brands of sand and could not find a list of elements in their sand to compare. Maybe all arragonite is made of this and it's normal? I just did not expect a kitchen fridge magnet to get covered with metal when I drug it through the sand in the bottom of my tank. Thanks again.

[dscount]

Ditto on ditching the lava rock. Doesn't do anything but add to your decor.

If you don't plan on a lot of snails and starfish then the sand is fine. You will need to address having some "real live sand or live rock" to help stabilize the tank. It's debated that some sand is useless. (I agree some is)

I know the whole "Testing" the sand is posted somewhere on the site. Vinegar I think bubbles in the sand you want.

[harmy4993]

Just curious which sand is usesless and why it is useless?

[cmor1701d]

Quartz playsand is fine. Many people ahve used it without problems. Some types of sand (sandblasting stuff) has more dissolable silica that MAY create increase diatom bloom. EVERY tank will have a diatom bloom when it's new. It may last a bit longer with silica based sand, but it will die out.

Aaragonite based sand comes from the ocean. It has the same trace elements that the sw mix you use to make sw for the tank. Those elements are NOT harmful. "cobalt, magnesium and zinc" are all necessary elements. Look at what is included in a salt mix.

[dscount]

Basically what cmor1701d said. Two flavors. Crepe stated it as well: "Play sand doesn't buffer at all. Silica is completely inert."

If you are not planning on the product you are buying to be used as a buffer then go wild. I personally go with marine sand that looks good and does something for the tank at the same time. The quartz totally will be just fine in a tank. It's mostly a Decor vs. Real Ocean type setup in tanks. Some folks will get livid that live sand is a "MUST HAVE" and others just plan the tank without. All about personal choice really.

[harmy4993]

You do realize all sand in a tank is live sand by the time your cycle is complete?

[cmor1701d]

Quite right Daniel. LS is just sand coated with bacteria. As for quartz vs. aragonite..

Beaches - Products of Waves and Sand from the USGS

I'm still in the camp that if your aragonite is buffering your tank, then you have other problems in the tank chemistry.