Ok... I boxed up your Texas holey rocks. I'm gonna upload pictures of the ones I'm sending you for your shellie tank.
I know these little buggers like to dig, so I worked on the base of two of these I'm sending, to make them sit flatter and be more stable. I did a little grinding and sanding on the bases, hope that doesn't violate the sanctity of holey rock for any purists out there, lol.
I'm a bit OCD and a perfectionist so I had to create a simulated 10 gallon tank so I could try out different rocks, arrange and rearrange several times before I could make a decision on the ones that would be just right, and as close to possible as your drawing.
Not perfect, but I think you'll like these, and I hope your little fishies do, too. One thing for sure.... your ph will really be kicking up there. In fact, when you do water changes you will probably have to do multiple small ones very frequently or you'll go swinging from 8.5+ with gh and kh out the wazoo to whatever your tap water is.
You might want to rig up a reservoir to be ready for water changes, and I can send you some small chunks that are such pure limestone they're like handling chalk. White powder gets all over ya. I wish I had thought of that, I could have stuck the pieces in the box.
The box is ready to go out in the morning when the post office is open.
Here's some pics:
I used construction paper to make the correctly sized bottom and backside of a 10 gallon tank.
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I took this shot from above so you could see the depth of the rocks. I have them placed back against the glass, so to speak, lol, but you can see that you could have them forward so the fish could go behind, if you like.
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Another angle of the front view.
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Turned the middle rock around so you could see the back side. I think that hole at the top is plenty big for them to swim through, if they want to, lol.
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I turned the right side rock around so you could see the backside of it. I like it the other way around, myself.
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The smaller rock on the left has lots of nice holes to stick plants in, as does the large middle rock.
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Boxed up and ready to go
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So you can get an idea about the size of that hole.
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