TheConstantGrower
Fish Fanatic
That looks FANTASTIC, im already planning my own now
the high pH was expected due indeed to the portland cement. don't worry, i did a lot of research before embarking on this project. there's a whole heap of articles on diy backgrounds over at cichlid-forums.com. generally it seems to take maybe a couple of weeks for the cement to cure, and the alkalinity to die down, after which fish can be slowly added. if for some reason this doesn't happen in my case, i will be applying some clear pond sealant. naturally i will not be rushing my fish into the new tank, and i will be testing the waters regularlyThe reason for the high pH could have something to do with the lime in the cement mix you were using. The cement needs to be sealed properly to stop this leaching into the water column, or not only will you have a very high pH but lots of dead fish due to the other chemicals leaching also.
Sorry to put such a dampner on what is essentially an excellent thread and DIY job, but if you address the above matter of sealing the cement then I think you'll find that the pH will remain the same as your tap. I would coat the whole thing in a clear pond paint.
Such as the product below
[URL="http/www.clearpond.com.au/go/our-product...=productDetails"]http/www.clearpond.com.au/go/our-product...=productDetails[/URL]
Regards
BigC