Dear fellow aquarists please advice which kind of filter is good with pros and cons and in overall, sponge filter or hang on back filter?
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Both are good filters, but a lot depends on the tank size and bioload. Sponge filters work well in smaller tanks with relatively low bioloads. They also make good secondary filtration in larger tanks with a primary power filter. They're really easy to maintain, and they don't produce a lot of water agitation and current (if that's an issue for your particular fishes).
The downside of the sponge filter is that it doesn't provide you with the option of chemical filtration, if you should need it. Also, you have to be very careful when cleaning a sponge filter to ensure that you don't disturb the beneficial bacteria that provide the biological filtration for your tank. In a relatively large tank. a single sponge filter probably won't process enough gph unless you set up multiple sponges or have a power filter in addition.
Hang-on-back filters are more powerful than sponge filters (they use an electric water pump instead of compressed air), and most are designed so that you can run chemical filtration media in addition to the mechanical filtration (usually sponges or filter pads) and the biological filtration (often a bag or cartridge of biomedia). They're pretty easy to maintain, too.
The downside of HOB filters is that the intake tube and outflow chute are very close to each other, which means that some filtered water gets pulled back in through the intake tube. Also, certain brands of HOB are designed so that you have to use the manufacturer's replacement media cartridges, which can get expensive over time (one of the better ones is the Aqua Clear, which has a really large media chamber that you can load with your own media).
Ultimately it depends on your tank size, setup, and bioload. I know people who have tanks in 55g range who use both an HOB on one side and a sponge filter on the other, and they seem satisfied with the arrangement.