Concrete..reef safe? fishy safe?

[mr_X]

i actually work at a concrete plant. i have an almost limitless supply of cement.
can i make structures out of this for in the tank?
i know silica based sand is not good for the tank, i dont know why, but i heard this.
if i use marine sand, can i make my own rock?
if so, should i use the slate based stone we use in concrete here (east coast USA) for strength, or just go with sand and cement?

 

[mr_X]

bump

 

[Anonymous]

From what I understand it causes a huge pH spike initially due to the (?)lime(?) in the cement. I would soak it in saltwater with a powerhead and several water changes before trying it. Silica is not bad for your tank, it just doesn't have the same buffering capacity that calcium carbonate based substrates do.

Some types of concrete are definitely reef safe. Large public aquarium tanks are built with it.

 

[mr_X]

ok....so if i soak it and check the ph..wait for it to level out, i'm good to go?
so you mean to tell me i am paying mad money for LR i am using as base rock, and i can create this stuff for nothing? 8O

 

[blackcloudmedia]

I have been an avid supporter of this. So far Ive done lots of research and havent found any negative sideeffects. You have to allow the cement to cure for 2 days. Then allow it to "cure" in freshwater, the larger the body of freshwater the better i.e. not a 5 gallon bucket unless you want to change the water every day. Allow it to cure for a couple of weeks, some sites say months but it doesnt take months. Then you are good to go. Im studying to see coralline preference of concrete now. You may see sites saying you can create holes in your concrete/mortar mix by adding salt granules to the wet mix then soaking it in water after it has dried. I have tried, tested this, and declared it a messy waste of time, the resulting piece is far too brittle and somehow the NaCl interferes with the calcification process of the forming cement. Dont bother with it. Also there may be a tendency for a piece of concrete to develope black algae. Quickly remove the piece upon notice. Black algae is a quick spreader.

 

[mr_X]

http://saltaquarium.about.com/gi/dynami ... tRock.html


here's some interesting info.

 

[Anonymous]

Concrete is safe if properly cured.

 

[Anonymous]

If you make the pieces the right size & shape you can cure them in the back of your toilet reservoir. Every fluch changes the water for you. It'll cure quick and save water.

NO BLUE STUFF! :lol: