Why not crushed coral subsrate

silvano14

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Hi there.

I have a question to the expert's out there.

Why are you guys recommending to use silica sand and not crushed coral as a substrate.

Surely the coral is more porous which means that more organisms can live in them.

Is silica sand not completely impermeable?

A recommendation was made on my tank to remove the crushed coral, rather course variety, and to rather use silica sand.

Hence my question?
 

Kanga

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Hi there.

I have a question to the expert's out there.

Why are you guys recommending to use silica sand and not crushed coral as a substrate.

Surely the coral is more porous which means that more organisms can live in them.

Is silica sand not completely impermeable?

A recommendation was made on my tank to remove the crushed coral, rather course variety, and to rather use silica sand.

Hence my question?
What size is the crushed coral you have in your tank?
 

Peter Bee

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hi sil

i think what you say is compleatily correct and would not swop for anything but lets see as you say what the experts say. after all silica sand is cheap so that might be why you use it instead of natural coral, then you have no real hidding place for micro nunnes to hide and spend all your cash on a huge skimmer.
peter bee
 

silvano14

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Kanga it is quiet course. Probably 4-5 cm long and about 2cm thick. Give or take.
 

Kanga

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RightTank.jpg


Ok I see, its not the fact that its crushed coral, its the size.

The problem is that you trap detritus in the spaces between the crushed coral, end result is increased nitrates etc.
 

Rod

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Crushed coral in my opinion is the way to go. I have never used silica sand in a marine aquarium! And never will!
 

Rod

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http://i151.photobucket.com/albums/s132/silvano14/RightTank.jpg[img]

Ok I see, its not the fact that its crushed coral, its the size.

The problem is that you trap detritus in the spaces between the crushed coral, end result is increased nitrates etc.[/quote]

Sorry I have to disagree, if you have high nitrates look for other causes. Just my opinion based on 17 tanks I run. Make it 18 forgot my nano.
 

Kanga

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Sorry I have to disagree, if you have high nitrates look for other causes. Just my opinion based on 17 tanks I run. Make it 18 forgot my nano.
Now how can I argue with that:p OK now you have made us pic hungry:lol:

Like I said, its not what the substrate is, thats the problem here, its the fact that the pieces that are big that traps the detritus. This makes it difficult to clean, thus a nutrient source which is not easy to export via your skimmer or water changes.

Fine crushed coral is fine by me.

I have crushed coral in my dsb mixed with sea sand, however its sugar grain size.
 

silvano14

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So if it was fine crushed coral it would fine.

Sorry I just don't like the look of silica.

Mind you at the price of crushed coral I suppose silica is not that bad.

I could always smash the big pieces and make them smaller.:lol:

Mind you 10-12 bags. Maybe not.

Just buy finer I suppose.

Could I use the coarse pieces in my sump?

I have fine filter media on top of the crushed coral.

Suppose if I go to the coast again I could steal some sand from the beach.
 

Kanga

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So if it was fine crushed coral it would fine.

Sorry I just don't like the look of silica.
Yes fine would be fine



I could always smash the big pieces and make them smaller.:lol:

Mind you 10-12 bags. Maybe not.

Just buy finer I suppose.
http://www.marineaquariumsa.com/showthread.php?t=2163

Nakoma did it:lol:, however I cannot condone the waste of good Peroni drinking time, it can be done:lol::lol:
Could I use the coarse pieces in my sump?

I have fine filter media on top of the crushed coral.

Suppose if I go to the coast again I could steal some sand from the beach
Def no coarse pieces in your sump please, Fine filter media?

what does your sump look like?
 

silvano14

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Will try get pics of the sump and post here and on the other thread.
 

DragonReef

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The problem with a coarse substrate is as Kanga has pointed out, it allows detritus to settle into it. Over time this builds up and can lead to nutrient issues.

Some people have had success, like Rod where is doesn't become a problem. It's also a horses for courses scenario. Softy tanks will like a nutrient richer enviroment and will out compete nuisance algae if densly stocked.
If you striving for sharper colours in an SPS dominated tank then you want to try and limit the amount of nutrient build up.
Other factors such and flow and skimming also influence this.

If you happy with it though then leave it be. If you start experiencing problems with high nitrates etc, the substrate would be places to start looking for the problem.

HTH.
 

Rod

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The problem with a coarse substrate is as Kanga has pointed out, it allows detritus to settle into it. Over time this builds up and can lead to nutrient issues.

Some people have had success, like Rod where is doesn't become a problem. It's also a horses for courses scenario. Softy tanks will like a nutrient richer enviroment and will out compete nuisance algae if densly stocked.
If you striving for sharper colours in an SPS dominated tank then you want to try and limit the amount of nutrient build up.
Other factors such and flow and skimming also influence this.

If you happy with it though then leave it be. If you start experiencing problems with high nitrates etc, the substrate would be places to start looking for the problem.

HTH.
I am going to agree with you on the point where you talk of Acropora and the ilk. I am a Discoma, Sarcopophyton and Xenia junky. The odd pieces of acropora I have had have always been brown. So perhaps I should pay attention and try it?:)
Will have to start by modifying a system, next year perhaps.
 

Kanga

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I am going to agree with you on the point where you talk of Acropora and the ilk. I am a Discoma, Sarcopophyton and Xenia junky. The odd pieces of acropora I have had have always been brown. So perhaps I should pay attention and try it?:)
Will have to start by modifying a system, next year perhaps.
And of course we would LOVE to see it:p
 

Rod

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Right I will strip a system down and start anew. The refurb was being planned anyway, this time I will set it up for SPS, something I have ignored to date. Will post as I go on. Will have to be a new topic!
 
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Peter Bee

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hi there kanga
i have been running big coral pieces in about 15 four foot tanks and two 3meter tanks one for 13 years, never had a problem, you catch the crap on filter wool before it goes into the coral, if you put small stuff in there it will clog up after a while, the thick stuff lets the water flow past and it will flush out i think or am i wrong.
thanks
peter bee
 

Peter Bee

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to follow up
please let me know if there is a better way of doing this. i am redoing all my tanks next year and would like to know if there is a better way to set them up.
thanks
peter bee
 

nakoma

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i have crushed some coral :razz: :lol: :lol: :lol: look under diy i have to agree with both coral has lots of micro pores that allow just the right type of bacteria to grow and that is why a coral reef is made up of alot of dead coral but because it is a tank and not the ocean lots of ugly nasty things rot been them rather take nice big pices of coral and build yourslef a nice rokry out of it then you have lots of bacteria
 

Kanga

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hi there kanga
i have been running big coral pieces in about 15 four foot tanks and two 3meter tanks one for 13 years, never had a problem, you catch the crap on filter wool before it goes into the coral, if you put small stuff in there it will clog up after a while, the thick stuff lets the water flow past and it will flush out i think or am i wrong.
thanks
peter bee
OK this is just my opinion and there are guys here who are much more equipped to answer, but here goes.

Yes, i am sure you can keep fish and corals like that for very long times ( the fact they are kept alive doesn't necessarily mean we are doing whats best for them), and yes I do think you will flush some of the detritus out, but some will stay and the rest of your system will just have to work harder to deal with the nutrient load

also having finer subrate in your display effectively turns it into a shallow sand bed ( another plus)

Also in all honesty ( and this is personal) I dont like the look of coarse crushed coral in a tank, i prefer sand or any fine substrate

to follow up
please let me know if there is a better way of doing this. i am redoing all my tanks next year and would like to know if there is a better way to set them up.
thanks
peter bee

I think fine subsrate where your bethhic critters can thrive is the way to go

IMO
 

nakoma

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i have to agree it just looks nicer never been a fan of very corse coral at the bottom of the tank fine crushed coral mixed with nice coarse very corse sand looks more natural and neater but i do think that crushed coral can hold more bacteria than just sand that is why i am going to mix the 2
 

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