Hello there.
Its a pity that nobody has answered your question, – I will try to answer as best I can.
First I can say that no, of course nothing has changed in terms of how paros are best kept.
What you describe sounds mostly okay, – but what is sodium bisulphate and why use that ??
You should definety add some leaves, for tannin but also for the fish to feel comfortable. Bare bottom is not in my mind the best always.
Regarding your question about feeding, – are you using live brine shimps ? Is that what you mean by baby brine shimps ??
Of course it depends on how many fish you have, – but for one tank with a few fish, you really dont need a lot. I feed every second day, – and only feed live artemia, – and I just add a tiny bit to each tank.
But its really difficult to say, – I doubt that is the reason that they died, unless you didnt feed live food.
There are a number of things that can go wrong keeping paros, so the reasons could be many