Question about Intex Krystal Clear sand filter system

Hello, would you rather use the 6000 or 8000 L/H pump for a 17'000L pool (549x274x132cm)? The difference in price is not that high, but on the other hand I don't want to have such a huge piece of furniture (I assume the 8000 is even bigger and possibly louder). At the moment I have the 4000 (at the old pool) but I see it rather at the limit or does the pool get clean everywhere it just goes longer? Would you also recommend a pool robot (ZX300) or is it also possible in practice with the landing net? Thanks & greetings