I found some 50lb bags of powdered hydrated lime close to me for $6.93 a bag. For that price I think it is worth a try. When it warms up a little I'll give it a try and post my results. Of course I plan on starting out real slow and monitoring the PH real close because I don't want to kill any fish. However, if it does seal the leak while killing all the fish...I wouldn't be too disappointed.
