ok substrate test inprogress.

[StirCrazy]

<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><HR>Originally posted by One_Divided:
the feedback I've gotten on it is that it may lead to silicates breaking down in the water and therefor more algea growth<HR></BLOCKQUOTE>

hey Adam I find the people that say this are old timers who don't know why they are getting algae and just blame it on the sand. Silica is glass particles and is insoluable in water. I was going to go witth sand blasting sand hence my "glass for a sandbed" post but all silica sand is sharp and not smoothed edges (if it was smooth it would be clear like glass) so that is why I started checking out the dolomite as it is calcium and IF there is any sharp edges it will be soft like calcium.

Steve

[StirCrazy]

ok from saturday night to now this is the results on the clearing. the left glass caribsea sugarsand (still cloudy) and on the right dolomite (crystal clear)


the only think I have noticed about the dolomite is a scum on the top of particles that will not sink, Victor did you have this? and if so was it easy to get rid of it? I imagin if I have a surface overflow set up and use a filter in my drain for the sump it should take care of it... I stired it a little to see how long it will take to settle out so I will do a ph test when it is clear again.

Steve

[reefburnaby]

Hi,

When I placed it in the tank, I got the lime foam. I just skimmed it away by hand. Eventually it will disappear proved that there is enough water circulation. Surface skimmer also helps.

- Victor.

[DJ88]

As a counterpoint to the dolomite testing, I have a few things that I am curious about.

At what pH does Dolomite dissolve? When it dissolves what does it break down into?

My reasons for asking this ar that in a proper DSB(4" or greater) the pH within the sandbed does drop enough to cause a normal oolitic or aragonite based sand bed to dissolve at a slow rate. Breaking down and releaseing the minerals and elements within the arqagonite into the water column.

What will happen when you get the proper de-nitrification within the sandbed going and the pH drops enough to dissolve the dolomite?

I am concerned that there is no real long term knowledge with what may happen in a DSB with dolomite. I have seen what aquarium grade silica does in a reef tank and it is fine. Dolomite is nice and white and is a fine particle, but what will happen in time? With everyone rushing out to try it I am concerned that in a few months we may see Victors tank crash due to the chemical composition of the Dolomite reacting in his tank. People rushing out to load this into their tanks may want to wait and let time tell.

But that is me.. Has anyone asked any chemists what may happen in an aquarium with this stuff in it?

later...

[reefburnaby]

Hi,

Limestone comes in may shapes, forms and composition. Aragonite and domilite are just two forms of limestone. Aragonite is mainly Calcium carbonate while domilite is a 60/40 split between Calcium carbonate and Magnesium carbonate. So when it does dissolve, aragonite disolves in to a Ca++ ions and domilite disolves in to Mg++ and Ca++. So...there is 60% aragonite in domilite (or so). But, I don't think a DSB will dissolve much faster than the rate at which magnesium or calcium is consumed -- in fact I think it is much much slower.


In fact, I would be more incline to say Domolite is better for reefing than Aragonite since Magnesium is leeched back in to the water column.

People have asked if domolite can be used in a reef before (check RC). Dr Ron and others seem comfortable with it. There are several people are using it too.

Anyway, I would try it if you are on a limited budget (like the rest of my little projects). Its like overdriving lamps...why do it if you can afford an HQI ? So, just keep that in mind. For me...its a hobby. I have fun trying to figure out why a DSB works and how come you need oolic sand to make it work. Is there a better way ? Cheaper way ? Environmentally friendly way ? What is necessary and what is ... just pure false information.

Say darren...don't you put domolite in your calcium reactor for magnesium supplements ? That is what I heard you have to do once in a while or your magnesium levels will drop too low and cause your tank to crash.

- Victor.

[DJ88]

Victor,

Thanks for letting me know what the composition of dolimite is. Was wondering.

If it is made up of those two go for it. [img]images/smiles/icon_smile.gif[/img]

<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote

don't you put domolite in your calcium reactor for magnesium supplements ? That is what I heard you have to do once in a while or your magnesium levels will drop too low and cause your tank to crash.

I don't add dolomite in my reactor and have never heard of that being put in. Or magnesium depletion causing a crash. For that matter I don't know anyone putting dolomite in a reactor. Can you show me where this is suggested?

To make up for element and mineral depletion I do regular water changes. The magnesium level in Instant Ocean is 1.296 ppm where natural sea water is 1.35ppm. Every two weeks I do a 20% water change. Or more frequent if I have it ready. Works for me. And many others.

I dont feel there is a need to do anything with additives other than what I get from those water changes and my Ca reactor. The only reason the reactor is there is for buffering and calcium addition for me. With teh added bonus of any minerals etc that may be contained within the aragonite.

<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote

What is necessary and what is ... just pure false information.

I am not saying aragamax is necessary. If it(dolomite) works go for it. As for being false info.. what is false info?

Envorinmentally friendly? lost me here.

I have no problem with experimenting with lighting, skimming and such. But for the sake of the corals I have and will have I'd rather go with the tried and true for the sand bed. It works for me and I am not hesitant to spend the money I need to get what works. If in time it is proven that Dolomite is a viable alternative I'd try it.

Right now.. Don't know.

My one concern is the fact it is mangnesium carbonate with calcium carbonate. If this is true what happens once you get the DSB functionning properly with the lower pH deeper in the bed? Will the mag carb dissolve? if it does what happens as these levels rise in your tank? If they get too high will it have any adverse effects? I know that my DSB is Calcium carbonate and how it interacts in my tank, I'll keep it that way. I can keep my mag levels up. But if it climbs so high that it is detrimental to your corals what then? Water changes yes, but even then due to the fact that the make up water has the proper levels already you arne't relly lowering the Mg levels. As the sand bed dissolves you get more Mg. After a while I can see axcessive Mg crashing a system before depeltion of Mg which will happen slowly with regular water changes.

As I see it right now you are the only one here who has an working knowledge of how this stuff is working. I have not seen anyone asking any questions other than how much does it cost? and how does it look? That is it. Nothing has been asked about interactions within the system. Other than by me.

It's one thing to try new things. It is another to just do it without asking a few questions.

[Aquattro]

I agree, Darren. Although it's a nice pretty white color, I'll go with aragonite oolitic sand just for it's reputation. After spending 5k+ on my tank, I'm not going to worry about the cost of a few bags of sand. There is way too much going on in the sandbed, both chemically and physically to "play" with new products. It may turn out to be the best thing ever discovered for reefs, but I'm not gonna be the one testing it. Aragamax is my friend!!

[StirCrazy]

ok sence I know you want to know Darren,
I started out with water that was a PH of 6.2 and a GH of less than 20ppm and a KH of less than 10ppm (this is well established fish tank water although not salt)
the results as of today are
sugarsand PH ~8.0 GH has increased to 180ppm
KH has increased to 100ppm

Dolomite PH 8.2 GH has increased to 120ppm
KH has increased to 100ppm

what does this tell us?
well lets start with the deff of GH and KH to make this easy to understand.

GH is the measure of desolved salts primarly composed of calcium (Ca) and Magnesium (Mg) also knowen as total hardness.

KH is Carbonate hardness (comonly knowen as alkalinity) is a measurement of the capacity for water to nutralize an acid, knowen as the buffering capacity.

now what do my latest measurments mean tome? well my results have showen that the two samples have raised the buffering capacity of a glass of water to the same point, but it shows that the caribsea raised the GH a lot higher. now sence GH primarly composed of calcium (Ca) and Magnesium (Mg)the results seam to imply that the caribsea sugarsand seams to be releasing either more calcium or magnesium into the water. now as I don't have either a magnesium test kit or a calcium test kit I cannot tell which one. if it is calcium that is great and a added bonus besides buffering. if it is magnesium then that means by using caribsea sugarsand you have been unknowingly aadding magnesium to your tanks which hasn't showen up as a problem that I know of. **** now I will say this as a disclamer as Darren was right in saying that I might me making dolomite sound better than sugarsand. if I have it was unintentional of course. I am mearly trying to find out if dolomite is "as good" as sugarsand.****

Steve

[powerreef]

Hey folks I know the delima to search for a sandbed that we all can afford. I have read the threads above and would have to worry a little bit about it. If this product has so much Mag. it in it will poisen your tank over time with the fact that it is Mag carbonate that would indicate that the carbonate Ion will dissapate the mag. more readily. Another thing is that this product is mined and sold with a completely different perpose in mind. I sure this product is more than likly to be cross-contaminated with whatever had been sitting next to it in the baggging facility or on the ground from where the dump truck left it, also what about metals from the collection process (crane scope, rusting dump truck, bulldoser). anyway just my thoughts.

Oh ya on the Mag. to obtain high levels of calcium in our tanks we add calcium carbonate (through either a reactor or additives) the carbonate ion causes the calcium ion to dissapate very quickly. What Mag does to help retain calcium in our tanks is that its ion coats the carbonate ion and thus slows the dissapation down so that the calcium can remain soluable in our water. Sometimes reef tanks just cant seem to get over the 300 ppm mark this is usually from a lack of Mag.

good luck
mike

[StirCrazy]

I have done some more serching on dolomite lime and I have found several things.

everytime Dr Ron Shimek is asked if dolomite is ok the reply is always the same
"Hi,

It should be okay providing:

1) that it has the appropriate grain size, and

2) that it doesn't have quick lime, or any such product or other contaminants in it.

In other words, if it is just ground-up dolomite, it will be fine. If it has been treated, it may not be.

If you can get some, toss it in some salt water and check the pH. If the pH rises above about 8.5, don't use it. "

also I stumbled on another thread from a old timer saying that dolomite was what everyone used befor caribsea started making sands for the reef as the only other thing they could find was crushed shells.

and to my suprise there are a lot more people using it that I thought.. a couple people with tanks running over 1 year on it and one over 2 years with no problems.

so while now with this new information (or old as it may be) and my test results I have decided that i wil use it in my tank. hell I will be the exparament in progress
[img]images/smiles/icon_biggrin.gif[/img]

but I have to wonder why people got away from it.. I never once found anything bad about "pure dolomite" and even the part about over dosing magnesium was downplayed as not a problem in a high PH and saturated solution such as sea water. which also goes with my tests as I used water with a starting PH ove 6.2

Steve