Ok as promised, here are the costs of things. Some other things like screws, glue etc that I didn't mentioned here means I already have them from previous projects (of some sort...)
1) 2x4 wood - RM25/8ft used 2 = RM50
2) 1x2 wood - RM7.20/8ft used 3 = RM21.60
1) Blue 36" x 30" x 10" fish tank - RM55 from aquarium shop
2) Thumb size pebbles (and smaller mixed) - RM20/bag used 8 = RM160 from landscaping shop
3) Piping (elbows, different size pipes, etc) - RM50 from hardware shop
note: you might want to refer to Affnan on what kind of materials you need for the syphon.
1) 80 gallon black poly tank - RM130
2) Astro 2000 water pump - RM55 (I found cheaper somewhere else - happened every time when you already bought something!)
3) Electrical conduit and elbows (to make as frame for the cover) - RM10
4) Black 70% shade - RM3.50/ meter used 1 meter = RM3.50
1) Junction box - RM15
2) 2 gang 3 pin socket with base - RM15
3) Electrical conduit - RM10
What else? I think that is it. So total damage is RM600 there about because I didn't put the cost of fish in there. If you already have tools, this is what you should be looking at if you want to build this kind of setup.
I also found that using LECA as medium could reduce your cost if you know where to look, plus your grow bed can be a lot lighter. Those pebble bags weight about 18kg each so do you math on how heavy my grow bed is! Next up, my tank cover modification so stay tune...