Cinder Blocks as Reef Support NEED HELP PLEASE!

[GreasyMidget]

We just this week got our 210g tank and set it up and my question is this. We are gonna use cinder blocks for our base so is there something that i have to do to them besides just rinse them off or bleech them? or can i just place them in the tank now?

The tank is brand new and there is no life except for a few shrimp that i am sacrificing to the Cycle gods..

I was wanting to get the base reef set up and then add live rock tomorrow if possible to get this thing kicked into gear. I would really like to put them in tonight but i have heard conflicting arguments on this issue and would like clarification by experience. I need to know if there has been anyone who has bought them and rinsed them off and then added them to their tank right off the bat.

What does vinegar do and what kind do i need to use? can i just dowse the blocks with vinegar or soak them directly in it and let that soak in to take out all the stuff that will make the PH rise?

[dendronepthya]

I too am in a similar boat. I am in the process of curing some cinder blocks. I am only using fresh water though, and letting them sit for weeks. From what I understand, cinder blocks are extremely basic, so they will drive up your pH. There may be other toxins that leach out into the water as they cure. I suppose vinegar would help neutralize the basic nature of the cinder block, but I think if there are any other chemicals that may leach out, only a long-term soak will really remove that stuff.

I have not successfully done the whole curing process yet. I have soaked my blocks for about 2 weeks now, and will wait one more week. In that time, I have drained my tanks twice. I suppose we will see in time whether I should have waited longer or not.

[dendronepthya]

I also want to point out that I am using a lot of water, so if I mess up, there is some "give" to my system's water chemistry. The system I am using the blocks in is about 750 gallons, and there are only 12 cinder blocks in there.

[GreasyMidget]

Excelent. i have asked around and some use muratic acid to cure them faster and vinegar as well in the fresh water that you soak them in. my tank is only a 210g so one would jack it up i am sure.

[kybreos]

You do know that you didn't have to use any live animals to cycle your tank. When you start buying real live rock whether it is cured or not there will still be stuff dieing on it that will cycle your tank. Just an opinion, other than that good luck and let us know how your tank turns out as well as how the cinder block curing goes.

[mellen]

I have been in construction/restoration for many years. Please understand that the mineral components for cement block vary by region and that waste blast furnace slag may be included in the Portland mix along with aluminum and iron oxide-rich silicate sand sources. These could cause problems in a tank. Check the yellow pages for masonry supply yards and ask about mined coral rock (a major export from FL, where I'm originally from). This fossil reef rock is used for road fill and decorative landscaping and can be worked into whatever shape you wish to support you live rock veneer overlay using common masons tools like cold chisels & masonry saw blades, etc. It will also colonize better than concrete block, and carry none of the possible leachate risks.

Another route to go is making shelving/tiers for your LR out of pvc plumbing pipe & joints. If you make the pvc shelves sturdy enough, just stack your LR on and around it. To attach LR to pvc for extra stability, use aquarium 2 part epoxy putty and cement anchor screws. Another, less desirable method is polyurethane foaming adhesive (you must use poly glue out of water and let it cure; mist the LR face with SW to lessen your die-off somewhat).

[GreasyMidget]

Thank you for the info its very helpfull.

[mellen]

I am very glad you saw my response...The original post caught my eye with great concern. Unfortunately, one must contact the source/manufacturer of cement block to check on ingredients, and even then, they may not know the exact composition of their raw material from THEIR suppliers, and so on back to the quarry. This kind of use for block (aquariums) is so uncommon. Pond keepers use block, but they always add a pond liner or use special pond paint to seal off the blocks, which is another thing you could do if you've already bought block/are on a tight budget/time constraints. http://www.aquaticeco.com/index.cfm/fuseaction/product.detail/iid/11733/cid/3035

By the way, that is the beau-coupe best source for anything you can think of aquarium-wise! Every hobbyist should add Aquatic Ecosystems to their favorite links list! 30,000 items...:rollface:

[Rip Current]

lava rock .....................I used a piece of lava rock for base and a year later I put it front and center because i looked better than some of the so called premium live rock and its really porious too

[robwsup]

I asked this same question a few years ago, and didn't get much response. I figured I'd scrub some and throw them two my 75 gallon. When I transferred to my 150, I added another 1/2 block. I used regular Home Depot 8"x8"x16" cinder blocks. I noticed no ill effects. Today, they are covered in coralline and star polyps.

This pic is about 14 months ago.
<img src="http://gallery.photo.net/photo/1751890-lg.jpg">

This pic is a few weeks after, when I transferred to the 150 gallon.
<img src="http://gallery.photo.net/photo/1751962-lg.jpg">

[GreasyMidget]

that is cool looking lol ! Lord of the reef the 2 towers! lol