Dishwasher soap in the US is garbage now, so you have to scrub anything that might possibly stick on, despite the wash cycle on my dishwasher taking nearly two and a half hours.
The tabs I use are environmental friendly. I.e. no phosphates, no palm oil, no chlorine. The wrapper dissolves in the machine (an algae-based polymer similar to what is used for capsules to deliver meds).
The packaging says:
15-30% bleaching agent based on oxygen.
<5% non-ionic surfactants
phosphonates, enzymes (protease, amylase), perfume