Thanks for the comments guys.
1. No problem with the Algae so far. The 36W UV lamp and the huge number of floating plants covering the top surface seem to be doing the job.
2. The red flower is Lotus (Nelumbo nucifera), not sure what the white color one is, probably an amazon variety. It has hundreds of flowers every morning and a very pretty sight. The leaves of all the plants are extremely large probably because of the nitrate supply from the fish.
3. I have built another sump (6'X2.5'X2) attached to the smaller sump I already have in which I'll be growing more water plants. With this extra sump the total water volume in the system would be about 650 gallons.
4. I've attached a few pictures showing the front panel, it is very difficult to get good shots because of the reflection of the sun light.