I'll start off with addressing macros here.
If you can get K2SO4 in Singapore, then do so. If not, you can probably top off the missing K+ with Seachem's Potassium. The 4 compounds you have listed there do not cover for the extra potassium needed on top of what they provide.
If you can't get any of those chemicals, you can use Seachem's Equilibrium, then top it off with Flourish K+ and Flourish N. I would not use this this method if you have hard water; I used to post over on AQ more frequently, and I know SG water varies a lot.
If you want to use Tropica Plant Nutrition, you can dose 75ml a week and then top off your K+ with some K2SO4 or Flourish K+. This will take care of everything in the most simple way, but is probably the most expensive route. If you have soft water, you may need some CaSO4 or CaCl2 to raise the calcium.
Now, as for micro nutrients...
If you use the first two methods I described, you can use CSM+B, TPN/TPN + or Flourish to accomplish what you need. I prefer CSM+B for price and iron concentrations, TPN/TPN+ used as a micro only works well but I'd use some chelated iron with it possibly. Flourish works on its own. If you can get flourish plus one other type of micronutrient, you can switch between the two to make up for any possible nutrient deficiencies that exist between the ferts and the tap water.
And finally, I looked over the LushGro line. I can't say I like the look of it as well as any of what I listed above, but if there's nothing else available, it's worth a try. The LushGro Aqua would need more N and PO4. The LushGro Hydro Solid looks good (copper levels shouldn't be a problem) but it would need more N and K to make up for its high PO4. The other lines didn't look too worth while to me. Either of these options would probably benefit from some LushGro Trace, or any other trace we've talked about so far.
-Philosophos