I have a 2.2 kw water-cooled spindle, I've created a reservoir of aluminum that can accommodate 0.75L water, will it by itself be enough to cool the spindle or should I install a radiator too?

The radiator I have is a 120mm with fan from a PC cooling kit. but i want to do without mounting it if I could, I often see that people write that 2.2KW Chinese spindles does not need much cooling but I'm not sure if I have enough water to do without a radiator.

1 reservoir -> pump -> Spindle -> reservoir

or

2 reservoir -> pump -> Radiator -> Spindle -> reservoir