Safety of cement in tank

Discussion in 'General Discussions and Advice' started by gmohr, 2 Sep 2011.

  1. gmohr

    gmohr

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    Hi All
    I read about aquascaping with cement. I have put a cement block in my koi pond before. Anybody with knowledge of any dangers of putting stuff made of cement in a marine tank? I would think that it be ok if cement is properly set (say after a week or two).
    Any ideas welcome.
     
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  3. dallasg

    dallasg Moderator MASA Contributor

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    it would need to be cured for 3 months or so, then to be safe it must be sealed and then i would say its safe, the lime can affect the PH if not cured
     
  4. leslie hempel

    leslie hempel Moderator MASA Contributor

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    basically the cement is a danger to PH as dallas has mentioned, by curing it in FW you reduce the risk of it swaying parameters..

    i have used concrete blocks for scaping in tanks before and it works wonders for creating a sturdy base structure when going high with scaping..
     
  5. gmohr

    gmohr Thread Starter

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    What can I use to seal it?
     
  6. dallasg

    dallasg Moderator MASA Contributor

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    u can use an ammonia free epoxy resin from builders warehouse
     
  7. Evo R

    Evo R

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    I have heard that un-cured cement can/will leach sillica back into your system, and push your phos sky high.
     
  8. gmohr

    gmohr Thread Starter

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    Just an update:
    I made a corner piece. Put it in my pool for two weeks then in my koi pond for four weeks. It has been in my tank for about three weeks now and all seems ok. The only thing that worries me about aquascaping with cement is the weight of the finished product. I think next time I will mix the cement with less water so that there will be more small hollows rather than compact cement.
    I just need to sort out a bit more flow in the corner.:thumbup:
    Cheers
    Geoff
     
  9. leslie hempel

    leslie hempel Moderator MASA Contributor

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    or add some PVC...

    Check this tank out, you would never say that these are pipes encased in rockwork..

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    PS: the ones that go all the way to the top are the overflows....
     
    Last edited: 1 Nov 2011
  10. mandarinman

    mandarinman

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    ive always wondered what would happen if you made cement liverock using icewater and ice cubes or chunky crushed ice. mix it shape it quickly let it set. when the ice melts you should have holey liverock?
     
  11. leslie hempel

    leslie hempel Moderator MASA Contributor

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    Amen? :lol:
     
  12. mandarinman

    mandarinman

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    from the hebrew word meaning verily or truly (amen).!
     
  13. SteveZi

    SteveZi

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    :lol:

    the majority of rock in my tank is old cement rubble, cured in the ocean.
    i get the feeling it may erode quicker than normal (aragonite/calcium based) rock.
     
  14. mupwi

    mupwi

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    nice idea with the overfows:thumbup: very covert
     
  15. seank

    seank

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    Cement gives off a chemical reaction when mixed with liquid, making it warm, it'll melt the ice before you can say.......ICE
     
  16. Braco

    Braco

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    this is amazing..very innovative idea with a very natural form to it..might be worth looking into something of this sort..;)
     
  17. leslie hempel

    leslie hempel Moderator MASA Contributor

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    i was skimming through the pictures on this thread and all the pipes within the tank made it look soo cluttered as there is NO LR in this system or the DT anyhow if i remember correctly.. then i went on further and found those images.. and it all made pervect sence..

    wish i had tagged the thread..
     
  18. belindamotion

    belindamotion Google Master

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  19. MistaOrange

    MistaOrange

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    I've made many frag plugs using white cement & aragonite which is cured for about a week & haven't had a problem with ph or po4. I try to use little water & using a drill with a diy mcgyver to airate the mix to create holes. Once cured I soak the plugs in saltwater changing the water every 2 days for a week then I put the plugs in frag tank until I need them. I'm suppose one can make base rock with the same mix.
     
    Last edited: 1 Nov 2011
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