Help! Sand for DSB.

[down and outman]

I've been teased enough about Southdown Sand on the internet. All the posts for it's availability are from 2004 and prior. SO, I've been investigating sand for my new 90. I've picked out Carib Sea Oolitic, go with about 3 -4 inches, BUT!, what about any play sand at Home Depot? I'm having a hard time justifying $22 + shipping per bag if I can use a couple of 50# bags at $3.49 each.

The products available are: Quickcrete Play Sand, and Pavestone Sand.
I got a sample of the Pavestone from a broken bag and will test it with vinegar. (thought about taking it to work and testing it with some Nitric Acid).

I think in the long run I should bite the bullet and get the good stuff, so does anyone have any recommendations?

BTW, My goals are Nitrate Reduction, ph balance, Good sand for sand sifters, raising corals, calcium content, etc.

[Witfull]

i used quikcrete. 300lbs in my 210. its silica based, and slightly tannish,,,,same color as beach sand. i dont really buy into all the "agronite talk" and "silica diatom fears" one thing with the HD sand, its kinda dirty and needs to be slowly flushed to get rid of dirt.

[mps9506]

Bare bottom
I have used playground sand as well with no long term issues. IMO it doesn't look as nice as the white stuff. I used it for a DSB and it worked. I didn't take good care of it long term though and discovered happiness with the barebottom tank.

[Witfull]

Originally Posted by mps9506

Bare bottom

i think this may be the only time RS will not ask for pics,,,after the grass skirt pic,,,i dont know how much more i can handle~

[down and outman]

Originally Posted by Witfull

i used quikcrete. 300lbs in my 210. its silica based, and slightly tannish,,,,same color as beach sand. i dont really buy into all the "agronite talk" and "silica diatom fears" one thing with the HD sand, its kinda dirty and needs to be slowly flushed to get rid of dirt.

The sand I used in my first tank was aragonite and was pretty dirty as well. I've learned to flush it out good before I put it in the tank. I got rid of it as I had crushed coral and regular beach sand (that caused a lot of problems, algae and snails didn't take to it). I'm still trying to decide, but I'm glad to hear that someone else has had success with it. My rock is cured and I salvaged the rubble so I can "seed" it to get it"live".

Thanks!!!

[mps9506]

Originally Posted by Witfull

i think this may be the only time RS will not ask for pics,,,after the grass skirt pic,,,i dont know how much more i can handle~

At least I had a bra on

Anyhow let us know how the sand works, I doubt you will have issues with it that you wouldn't have from any other sand.

[PhilOlsen]

You need to make sure the sand you choose is safe, meaning no silicate etc.
Here is a 100% sure fire way to tell:Shot glass full of vinegar, pinch of sand.
If the sand bubbles, it is aragonite, if it doesn't, it is not.

[Witfull]

SILICA IN REEF AQUARIUMS by RANDY HOLMES-FARLEY, Ph.D.
http://www.advancedaquarist.com/issu...03/feature.htm

Silica is a chemical that is feared by many reef keepers. Visions of a reef tank covered with diatoms so thick that you can’t see through the glass come to mind. More recently, others have suggested that soluble silica does not, in fact, increase diatom growth in reef tanks. Much of the debate swirls around whether silica sand is a good choice for the substrate in a reef tank. According to different individuals, it can easily release soluble silica, or it cannot possibly do so. In this case it appears that the truth is somewhere between these views....I’ll also show with dosing experiments that soluble silica is rapidly depleted from my reef tank (about 50% per day). When adequate silicate is added to my reef tank, diatom growth appears to increase. Contrary to popular notions, however, the increased diatom growth actually makes my glass easier to see through than the green algae that it replaced.

Finally, and I think most importantly, I’ll recommend that people consider dosing soluble silica to their tanks to support the variety of organisms that potentially use it, from sponges to limpets....

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.

In subsequent sections of this article I describe dosing recommendations for adding soluble silica. Is silica sand a good way to go from that perspective? I cannot really answer that. It probably provides some silica to reef tanks, but the amount is completely out of the control of the aquarist. For that reason alone, I believe that it would be a poor choice as the sole source of soluble silica for a reef tank. In a tank without any silica dosing, silica sand may, in fact, be more beneficial to the overall tank, at least from a silica delivery standpoint, than calcium carbonate sand. There are, of course, many other differences that might be the deciding factor on sand choice (color, texture, dissolution, particle size distribution, nutrient and metal binding properties of sands, etc). Many of these factors are more aesthetic than technical, and the technical ones are beyond the scope of this article.

[PhilOlsen]

Here is some info I found about silicates.

http://www.reefs.org/library/aquariu....html#silicate

How does Silicate and Silicic Acid get into your Aquarium
Many water sources contain silicates or silicic acid, or compounds that contain these elements and these compounds eventually break down, adding silicates and silicic acid to your aquarium's water.

In aquariums where sandy or other forms of substrate are used, silicate can leach "out" of these compounds, and enter the tank's water very quickly. It usually only takes a few weeks for this to happen (at the maximum). Often it happens much sooner. The latter is especially the case if silica sand is used as the substrate in the aquarium (this is too often the case,unfortunately). Although less common now than a year or so ago, hobbyists were adding "play sand" to their tanks to build up a substrate. Play sand and so-called Blasting sand are very high in silicate and should be avoided if you wish to keep silicates low.

I have made reference to removing silicates and silicic acid from the water. Please understand this to mean that you should attempt to keep their levels as low as you can. You will never really be able to remove "all" of these compounds. Recommended safe levels are below 0.5 ppm, or half of one part per million.

These silicate compounds then start building up in your tank's water since nothing is removing them, unless you actually take some measures to prevent them from doing so. When they build up to sufficient levels or concentrations, brown algae start to appear in patches first (often on the glass or acrylic panes of the tank). Mind you the patches can be hard, filamentous, slimy and can take on various other forms, depending on which particular diatom is growing in the tank.

The real dangerous types are the encrusting diatoms. They often populate the base of corals and grow upwards, pushing the polyp away from the skeleton. Receding of the coral then takes place. This is a real bad situation as, if this continues, the corals will recede more and more and will start to disintegrate, get infected, and you will loose the coral altogether.

Do not underestimate this danger. This can happen in a matter of a few days. I have personally seen an Elegance coral being overgrown by diatoms on its skeletal base and become totally wasted in a matter of 5 days.

Many hobbyists are under the impression that using reverse osmosis water or deionized water will solve the problem, and that doing so will remove the silicates and silicic acid from that water. This is, unfortunately, not the case. Such units, even if combined, will remove silicate and silicic acid for a very short period of time only and, then, the silicate and silicic acid will get through the membrane and the resins and will start to build up in the tank.

By a short period of time I mean in a matter of days, depending on how much silicate and silicic acid the water you are treating actually contains. Tests have shown that, when treating water with 14 ppm of silicate, the silicate and silicic acid came through the membrane and the resins used in combination with the R.O. unit, after less than 100 gallons of water had passed through the filtration set-up (lab. notes ref. 95/6/-012)

This is really not much water when you consider that most hobbyists believe that using reverse osmosis, deionization or a combination of both, gives them water quality of very high purity levels. Obviously this is not so, and that belief is a totally false one". R.O. and D.I. remove silicates and silicic acid for "some" time" only, after which the membrane of the reverse osmosis filter and the resins in the deionizers let the compounds through.

The conclusion to draw from this is that, regardless of how you filter your water, silicates and silicic acid will find their way into your aquarium's water, and you are going to have to take steps to remove it. This is discussed in the next section for both the water in the tank and the raw water. If you do not, diatoms will appear in your tank.

[mps9506]

this is why I bare bottom it (and I like the feel of the cool breeze throu.. ahem I mean...)
I think this is a key point:

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.

I personally had no excess diatom issues in my tanks that never occurred in any other tanks I had. Maybe it was because it was processed and "sterilized" play sand intended for playgrounds. I don't know but it worked as a DSB until I discovered the difficult way you have to maintain a DSB.

By a short period of time I mean in a matter of days, depending on how much silicate and silicic acid the water you are treating actually contains. Tests have shown that, when treating water with 14 ppm of silicate, the silicate and silicic acid came through the membrane and the resins used in combination with the R.O. unit, after less than 100 gallons of water had passed through the filtration set-up (lab. notes ref. 95/6/-012)

According to that I'm loading my tank up with silica anyhow from my source water.


Maybe it's all snail food in the end?

[Cougra]

Originally Posted by PhilOlsen

The conclusion to draw from this is that, regardless of how you filter your water, silicates and silicic acid will find their way into your aquarium's water, and you are going to have to take steps to remove it. This is discussed in the next section for both the water in the tank and the raw water. If you do not, diatoms will appear in your tank.

Well, since the silicates are going to be there anyway, why worry about adding them to the tank.

Seriously, I a lot of people don't like diatoms for some reason. Yes there are some that CAN be harmful but there are animals in our tanks that can be harmful as well. I've used silica sand and river sand in many freshwater tanks with very high and very low pH levels and haven't had issues with uncontrollable diatom outbreaks. I've also used "play sand" mixed with my South Down Sand "Tropical" playsand in my reef tank for the past three years and have yet to see any issues with diatom outbreaks in the tank. I haven't had major algae explossions, my corals hadn't misteriously shrunk out of site.

The fact is there are a lot of other compounds, pathegens, irritants, and undesirables in the tank that could cause the same or even worse problems then silicates. If you're worried about silicate acid driving down the pH in the tank, well CO2 is a much bigger concern IMO.

I know that my tank isn't perfect, that's why I do regular water changes, to help remove some of these undesirables that can't be filtered out so easily. Sure I may be adding some, but I'm not adding as many as I take out!

Diatoms are always in the tank. Most diatoms are free swimming meaning that they live in the water column. When you start seeing a thin film of diatoms, they are mostly dead and falling out of the water due to lack of food for them as a way to balance out the population. The most effective way to remove excess silicates is to remove the dead diatoms and animal waste from the tank! They are one of the many building blocks of life and many animals feed on then, from plankton to larger animals such as filter feeding worms (feather dusters), corals, snails, sea urchins, corals, starfish, gobies and the list goes on. In a lot of cases snails actually PREFER diatoms to algae!

It must be nice to have the perfect tank set up with the perfect water chemistry without any excess nutrients or compounds! I must admit I have to admire the person who is able to take every peice of conflicting advise, theory and supposition and build themselves a perfect tank. Me, well, I just aim for a good balance and enjoy watching the healthy animals rather then stressing about the elevated silicate levels in my tank!

[Witfull]

They are one of the many building blocks of life and many animals feed on then, from plankton to larger animals such as filter feeding worms (feather dusters), corals, snails, sea urchins, corals, starfish, gobies and the list goes on.

hmm....could this be why my tank is looking good?

[Cougra]

Originally Posted by Witfull

hmm....could this be why my tank is looking good?

No, couldn't possibly be, they are the scourge of the marine tank! Haven't you heard how harmful they are to everything? :smck:

[down and outman]

Took the sample of sand I got from Home Depot and sure enough, no reaction. I think I'm gonna go bare bottom for now and get some Carib Sea sugar sand after I lick my wounds from this project. I really liked the way my tank held it's ph when I had aragonite in it and I'd rather set it up right than have to dig all that crud out later on. Thanks for all the info. Now I need to make up about 90 more gallons of saltwater to fill this tank.

[Frankie]

I have to agree with Cougra: Quote-
I just aim for a good balance and enjoy watching the healthy animals rather then stressing about the elevated silicate levels in my tank!