Appropriate rocks to use???

[poolplayer]

Hi everyone.

I'm wondering if you could please recommend a source to purchase some showpiece rocks to put in a discus tank that will be clean, carbonate free, and attractive to look at. I have a 420+ gallon tank to scape. I will have some driftwood and a few plants but I'd really like 1 or 2 basketball sized rock showpieces.

Thanks!

[Altum Nut]

Here is just an option....https://www.universalrocks.com/
I think they had a display at the 2014 Nada show in Texas.

...Ralph

[pitdogg2]

you can also go to your local landscaping, Concrete companies and have a look around many do carry Granite and quartz type rock you may see something that catches your eye.

[poolplayer]

I've actually been told that all three of those (granite, quartz, and marble) are likely to contain carbonate which would make them inappropriate for use in a discus tank. Can anyone confirm if that's accurate or inaccurate. I know a lot about fish and chemistry but not much about geology:)

[pitdogg2]

yes scratch marble.

I have used both red granite and quartz in aquariums and have not noticed any pH shift. My quartz was large chunks of Tigers Eye and Amethyst both were in slightly acidic water for years with no erosion of the rock.

there really is no reason to keep Discus in low pH if you are going with domestics, Wilds I can see keeping in lower pH but most do very well in 7.0+ water as long as the pH is stable and not bouncing all over the place. That is where you run into trouble.

[DJW]

When I collect rocks I put a drop of muriatic acid to see if it fizzes. The API nitrate bottle #1 is an acid if you don't have muriatic.

[nikond70s]

petrified wood looks really nice in aquariums. wood that looks like rocks. or those big bolder round rocks would look nice. ones people use for cichlid tanks. home depot or your local landscape stores should have it.

and if i remember correctly, any rock is fine as long as it doesnt fizzle when u pour acid on it.

[poolplayer]

If domestic discuss are kept in neutral pH water such as 7.0, is it then acceptable to use rocks that may react to slightly acidic water? Not sure yet what my tap water will test out as, but maybe it will test out at 7.0, 7.2, or 7.4. If that is the case then are components such as marble or other carbonate containing rock acceptable? I can't imagine the buffering capability of rock with minimal carbonate could buffer much volume beyond a neutral pH, but maybe I'm wrong. I still wouldn't put pure calcium Carbonate rock in the tank but maybe those rocks that contain just a bit of carbonate are ok in those situations. Just a thought to ponder:)

[RogueDiscus]

I used to have a nice big white chunk of quartz in a tank without problems. Made a nice centerpiece. I've also used granite river rock, those smooth ovals. It's not always legal to take it from waterways though, depending on where you live.

[DJW]

If domestic discuss are kept in neutral pH water such as 7.0, is it then acceptable to use rocks that may react to slightly acidic water? Not sure yet what my tap water will test out as, but maybe it will test out at 7.0, 7.2, or 7.4. If that is the case then are components such as marble or other carbonate containing rock acceptable? I can't imagine the buffering capability of rock with minimal carbonate could buffer much volume beyond a neutral pH, but maybe I'm wrong. I still wouldn't put pure calcium Carbonate rock in the tank but maybe those rocks that contain just a bit of carbonate are ok in those situations. Just a thought to ponder:)

The solubility of calcium carbonate decreases as the pH increases, but it will still be dissolving at pH over 7. When people use crushed coral as a buffer, the trick is to find the right amount. If you put a whole lot of it in the tank, the pH will quickly go up to about 8.2 and stop there. If you need buffer, you want a small amount that is dissolving at the same rate the biofilter is producing acid. Too much and the pH will go up and then at the next water change you would have a sudden pH shift. It also makes the water harder.

[poolplayer]

The solubility of calcium carbonate decreases as the pH increases, but it will still be dissolving at pH over 7. When people use crushed coral as a buffer, the trick is to find the right amount. If you put a whole lot of it in the tank, the pH will quickly go up to about 8.2 and stop there. If you need buffer, you want a small amount that is dissolving at the same rate the biofilter is producing acid. Too much and the pH will go up and then at the next water change you would have a sudden pH shift. It also makes the water harder.


Makes sense to me:)
Thank you!

[Filip]

I use Lava rocks in my tank .They can be black or reddish in colour and most importantly they are chemically inert.

[poolplayer]

I use Lava rocks in my tank .They can be black or reddish in colour and most importantly they are chemically inert.
Awesome idea!!! I totally love the look of Lava rocks but kept forgetting to ask about their use with discus. If they're inert then that's perfect. They're usually a bit jagged but I'm sure they could be smoothed without much difficulty. Any good source to buy Lava rocks??

[Filip]

Awesome idea!!! I totally love the look of Lava rocks but kept forgetting to ask about their use with discus. If they're inert then that's perfect. They're usually a bit jagged but I'm sure they could be smoothed without much difficulty. Any good source to buy Lava rocks??

Here is an old pic of my tank with red lava rock , just for a reference:

101577

They are sharp ,but honestly I never had problems with discus running in to them . It seems to me like discus learn their environment pretty quickly and in case of emergency they swim very fast and accurately right next to the obstacles.
BTW lava is so lightweight and porous that you can cut them apart manually , and reshape them as you like.

I got mine directly from the nature (an old volcano mountine) but I'm sure you can easily find them in any garden supplies or centers.

[Ryan925]

My parents just bought a big property in north east California. There is beautiful lava rock scattered everywhere.

In my tank I use seiryu stone. I've read it can have affect on chemistry in low ph instances. I don't find any evidence of change in my tank. My ph is always stable at about 7.6

[Ryan925]

Here is an old pic of my tank with red lava rock , just for a reference:

101577

They are sharp ,but honestly I never had problems with discus running in to them . It seems to me like discus learn their environment pretty quickly and in case of emergency they swim very fast and accurately right next to the obstacles.
BTW lava is so lightweight and porous that you can cut them apart manually , and reshape them as you like.

I got mine directly from the nature (an old volcano mountine) but I'm sure you can easily find them in any garden supplies or centers.

Filip that tank looks great and that discus is amazing!!

[Filip]

Ryan

Filip that tank looks great and that discus is amazing!!

Thanks Ryan.
This was my last surviving discus from my previous batch of discus fish . This was the time before I joined SD forum and before I realize that I have neglected many of their basic needs .
They were kept in high tech fully planted tank with injected co2 and although the tank looked cool to me the discus succumbed to the bad conditions and died one after another.

[DanDiscus]

On top of what has been said in favor of Lava Rocks I would like to add his porosity. It will provide a high surface per area for aerobic and anaerobic bacterias, more than most of the other rocks with the same size.

[Filip]

On top of what has been said in favor of Lava Rocks I would like to add his porosity. It will provide a high surface per area for aerobic and anaerobic bacterias, more than most of the other rocks with the same size.

Yes that's right Dan. Many people still use crushed lava rock in their filters as a bio-filter material , although it is said that its capacity is allready surpassed by many modern bio material products in terms of" surface area per square inch ".