Cheers for that... We are mixing a waterproofing here with the concrete called Sahara..Also the final 1/2 inch will be close to neat cement with the Sahara mixed in too..
I`ll let it all cure for a couple of weeks before putting in water and then I`ll run it through the pump and filtration with loads of charcoal to get rid of the nasties..Probably for another 2/3 weeks.. Then I`ll stick the plants in and let them develop before adding fish..
Hopefully it should be OK by then..
What do you think?