Clown Loaches in a 200L Tank

[Beanz1927]

I'm new to fish and was wondering how long 4 Clown loaches could live in a fluval Roma 200 with 2 angel fish until they needed to be moved to a larger tank
Thanks for your help.

[Diana]

200 liters is not too far off of 50 gallons, (I tend to think in gallons) and this is a reasonable volume of water to dilute the waste for the fish load you are asking about. If the tank is long and low rather than tall, then this would be good until the Clowns reached around 4-5". Is the tank at least 1.3 meters (4') long?
Angelfish are fish for slow moving water, and Clowns prefer faster moving water. I would plan a filter to move about 2000 liters per hour, and have enough driftwood, plants, rocks and such that the Angels can find a quiet area.