What is the feed required for the following fishes?
(a) Catlas (b) Rohus (c) Mrigals (d) Grass carp

Explanation

### Step-by-Step Solution:

1. **Identify the Fish Types**: The question asks about the feed required for four types of fish: Catlas, Rohus, Mrigals, and Grass Carp.

2. **Feed for Catlas**:
- Catlas are known as surface feeders.
- They primarily feed on plankton and other small organisms found at the surface of the water.

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