Silica sand?

[wiggie89]

Every one is telling me that silica sand is terrible. That it is bad for your reef. But no one can tell me why. So I am going out on a limb and going to the advanced section. Maybe I can get a good answer here.

 

[Travis L. Stevens]

It technically isn't bad for your reef. Silicates will not leak out of the sand. After all, it's just mainly quartz crystal (Silicon Dioxide, SiO2). If it was a problem, then your glass would leak silicates. Heck, some people are even dosing silicate.

Now, the biggest problem is it can scratch your glass if it gets stuck in between your cleaning magnet or scraped against the glass. Another con is that it doesn't look very natural. And worst of all, it does not dissolve and act as a pH/Carbonate/Calcium buffer when your system is not properly balanced. For example, the pH drops to 7.5 because of Alkalinity and Calcium issues. On a positive note, it is always available and for a cheap price.

 

[wiggie89]

So making rock out of it isnt all that bad for your tank. I will still use sand without it for bed but if I wanted to make rock it would technically be ok?

 

[Travis L. Stevens]

It sure would. Once again, the rock would have a higher chance of scraping your tank, and you don't gain the buffering ability. But making your own rock with it isn't going to hurt anything.

Now on a different note about making rock is how porous it will be for biological filtration. If you make a big solid rock, then you won't get good denitrification, if any. If you can find a way to make it super porous, then your good, though.

 

[wiggie89]

Yes I read on one thread to use noodles. In the curring process they will dissolve. And if there are any throw it in the refugium and all your pods will eat them up. I also heard pvc shavings will do the trick because algea like plastic and there are light.

 

[Travis L. Stevens]

I never did try PVC shavings, and I really don't see much of a difference between that and using crushed coral or crushed oyster shell. I did try using noodles. And while it left interesting shapes, it did break apart the rock as they expanded in the curing process. So, be forewarned if you make a center piece rock with noodles and it breaks apart. On the other hand, though things didn't go as planned with my many batches of DIY rock, I would say that it wasn't too bad

 

[wiggie89]

That looks good, How did you come up with the shapes of the rocks just designed them in a styrfoam box or make them by hand cause those look real. If you dont mind me asking what was your ingredients. 5 parts coral and 1 part cement.
justin

 

[Travis L. Stevens]

Well, it's actually multiple batches. There are rocks with flat bottoms, rounded rocks, and porous rocks, and about three or four pieces of live rock.

The first batch was a test run. It was a mix of crushed oyster shell and cement. I just grabbed a small clump of cement, dropped it in a cookie sheet and repeated the process until I got a decent, random piece the size I wanted. Of course, it had a flat bottom. The flat bottoms are being used straight against the glass and in the substrate for the rock to sit on. The dip between the Kenya tree and Monti Cap frag, and the zoanthids sit in one that are directly under the return are little places where those large macaroni shells broke the rock.

The third and final batch is my favorite. It is completely different in composition. It's about 4 parts Rock Salt to 1-1.5 parts Portland Cement. It's more expensive to make though. I just add enough cement to make it the texture of cement. I was able to drop it on a cookie sheet for random shapes, let it dry slightly, pick it up, and round the bottom. Once cured it was VERY porous. I broke one in half and after about three or four weeks, almost all of the rock salt inside had dissolved. I was worried about the left over and contacted Randy Holmes-Farley and he reassured me that a trace amount of NaCl would not harm the aquarium. The inside of the new batch looks almost like lava rock in how pourous it is.

My next batch will be aragonite sand, rock salt, and portland cement to see if I can get as close to natural rocks denitrification ability and buffering ability.

The second batch was cement, crushed oyster shell, and noodles. This was where I got some wierd shapes because of it breaking during the curing process. It turned out to be somewhat porous. It's in a few places here and there

 

[wiggie89]

Wait so the third batch was just cement and salt. No sand or anything else. What kind of rokc salt. Could I uses sea salt that I use for my tank.
Justin

 

[Travis L. Stevens]

I have no idea if there is a difference in sea salt and rock salt. I just got the Rock Salt used for ice cream making at Wal Mart. It's right by the Mrs Wage's Pickling Lime at our store.

 

[wiggie89]

Wow where did you learn that salt trick. It is pretty smart. If you thought of it you should post it I am sure people would like to know. Do you have any pictures up close of the rock?
Jusitn

 

[Travis L. Stevens]

I thought of it when I was brainstorming of things that dissolve readily in water. It started with the thought of sugar, but there is a slew of problems with excess sugar and the availability of large, multi-sized granules. Then I thought of salt. Made a batch without caring if it's good for the reef or not, but to see if it worked. It worked better than I thought and asked about residule salt. Was told it was fine. Then tossed it my tank. Everything has been fine for months.

I don't really want to let the cat out of the bag yet. I would hate to say "Hey, This works!" and then six months down the line my tank crashes. I'll try to get pictures tonight for you.

Edit: That first sentence was supposed to say "I thought of it when I was brainstorming of things that dissolve readily in water, because I was so disappointed with the noodles."

 

[wiggie89]

Thanks

 

[Travis L. Stevens]

Feel free to give it a shot. So far so good with my tank for about 3-4 months.

 

[wiggie89]

Yea I deffinatly will. Do you think I can mek them in a tote with the same salt to give it a real natraule look.

 

[wiggie89]

Ohh yea what cement did you use.

 

[Travis L. Stevens]

Portland Cement Type 1. It's located in the back of our Lowe's in a 94lb bag. I hear that there is a portland cement type 3 that is white and very hard to come by. I really wish I read that whole thing, because now I can't find it.

 

[wiggie89]

How Long did you cure it for

 

[Travis L. Stevens]

Until the pH was a stable 8.3 or lower. It took about four to six weeks. I had multiple tubs that cured at different times. If you are just adding a little bit of rock, you can just pop it in the tank. I'm talking like a rock or two. Not half a tank full

 

[wiggie89]

I am planning to fill up my hole 55. I have a 5o gallon rubbermaid and a 70 gallon one. ZCurring will be a jiff