Permacon pavement blocks

[hamstercaster]

This may seem like a strange question but actually it is not.  I was wondering if anyone know if these blocks are safe to put in my tank.  I am getting two shell dwellers tomorrow and want to "re-aquascape" my tank to make it more welcoming for them and was planning on using permacon blocks.  Of course I do have some type of a plan to make them pretty much invisible.  I thought of using these cause they would make my life much easier and cheaper to build some caves and all for them.... So, should I go ahead with my plan?

[mila]

What shell dwellers are you getting?
Is there other fish in the tank?

[hamstercaster]

Altolamprologus sp. "Compressiceps Shell" Sumbu Dwarf is what I'm getting.  I have some Zebra Danios in my tank right now but have been told that they would fare well since they are more open water fish as opposed to the Sumbu who is a bottom fish.  I will eventually get more tangs though.

[mila]

For two Sumbu males you need caves, each one need its own territory. You can add few bigger shells, but males don't use it much.

[hamstercaster]

I think I need to rephrase my question lol... I meant, are Permacon blocks safe to put in my aquarium as I want to use them to make caves... sorry about the confusion... I have edited my post 

[kennyman]

They will add to the calcium hardness of your tank for sure. The dye may leach a bit from them as well.

[hamstercaster]

They will add to the calcium hardness of your tank for sure. The dye may leach a bit from them as well.

Which is bad or not harmful for the fish?  And if I take the grey Permacon.. I don't think that there is dye in that color... but not sure.

[kennyman]

All I really know for sure about the stuff is what you would learn if you spent three summers cutting 1,000s of pieces of the stuff for interlock patios. You need to wear a mask because the dust will turn to cement in your lungs and it gives you bleeding nose. It is like lime dust which is also very bad for you. I am pretty sure that the slurry of dust from cutting with a wetsaw is Caustic. That is very high PH. That is why I think it will raise your hardness for sure.

I would not be surprised if the blocks had a Ph over 10. You could test it by taking a piece, grind it up with a hammer a bit and put it in a cup of water to see how it affected the Ph.

[hamstercaster]

ok, thanks for the heads up Kennyman.. I think I will reconsider my options then.

thanks again

[oenology]

My sumbu dwarf male  hangs out in and around a large shell. My pair have bred many times in it but unfortunately none of the fry has ever survived past a certain size.

[Adam]

I would be worried about having something that could turn to concrete in my aquarium.

Adam

[hamstercaster]

Yep I guess it could be a problem indeed.  It's too bad because I had what I think were good ideas to create caves and all.  It would have made quite a unique set up I must say.. ah well, I guess I'll stick with natural rocks instead and give it my best to do something spiffy with my tank 

[mila]

I would be worried about having something that could turn to concrete in my aquarium.

I know many people using/making concrete backgrounds, specially for African lakes cichlids.
Check Cichlid-forum DIY section, or http://angelfreaksaddiction.myphotoalbum.com/albums.php

[dpatte]

i wouldnt risk it

[hamstercaster]

Now I just don't know what to do.  Indeed, many are using concrete for DIY backgrounds and they don't seem to have any problems.  Permacon is indeed concrete and I presume that it would not brittle much as it is done to sustain rainfall and snow after all... and I don't think it would turn the water to concrete or anything.. but at the same time, I am a bit weary of it's effect on ph as Kennyman said earlier in the post.  I mean, my ph is at 8.4 now so if it would buffer it upwards to 8.6 or 8.7, that's not a problem.  If it buffers it up to 10, then that becomes a problem.  So although I think I had a really good idea, I may just stick with good ol' rocks although I may by one block at 67 cents and leave it in a pail of water and see what happens and decide at a later date if I'm willing to risk it or not....

[kennyman]

Cement back grounds/ornaments need to be cured to leach PH effecting materials out. The blocks are probably not much different. I painted a pretty ugly picture of them but I suppose that has to do with how terrible a job cutting them with a concrete/asphalt saw all day can be  .

They are pretty limey. If you want to see how bad they effect your pH test one out in some water.

Making features from cement is doable, you just need to read about the curing process and accept what it will do to your water parameters.

[Adam]

I know many people using/making concrete backgrounds, specially for African lakes cichlids.
Check Cichlid-forum DIY section, or http://angelfreaksaddiction.myphotoalbum.com/albums.php

I've read about them as well.  They are put into the aquarium after they are concrete and have been leached.  Something leaching lime into an aquarium could potentially (maybe not) turn very low levels of water and sand into a hard paste.  Almost surely not enough, but you never know.

Those backgrounds are also soaked for a month or more with countless water changes before usage because of the pH buffering effect...

Adam

[hamstercaster]

Kenny and Adam, thank you so much for the last two answers, it sheds more light on the subject and I don't think it's worth the risk and time.  I wanted to use them as an easy cave making material and all and dissimulate them under gravel etc so it's just not worth the trouble.  I'll figure something out when I find rocks that I like. For now I'll use rocks and try and do something decent... the tank will be a work in progress much to my spouse's demise lol