Next plans - cement tank

I am planning to get a cement tank, longer than tall a little wide, should be ideal for having plants that grow out of the tank and will house a few guppies and other fish that I want to grow out. Currently I am looking for places where I can get such a tank or have something made.
I have seen some places on Sarjapur road leading to Agara circle, where there are folks who make pots for plants. Planning to check them out. Suggestions welcome.