1.  About eight teaspoonsful of Marine salts dissolved in a gallon of fresh water will afford a suitable hatching medium.

2.  As evaporation is rapid, the chamber beneath will require regularly topping up with fresh water.

3.  As Lake Powell filled, the flow of fresh water below it was greatly reduced.

4.  Asexual species tend to be small and live at high latitudes and high altitudes, in fresh water or disturbed ground.

5.  Ask a student to add more fresh water to the container.

6.  Breeds on still and slow-moving fresh water with dense fringe of vegetation, also Marshes, fens, bogs.

7.  Fortunately, this can be accomplished to a degree in an isolated aquarium without necessitating the circulation of fresh water.

8.  Fresh water rotted natural fibre, while seawater preserved it.

9.  Golf, boat trips, coach trips, riding and both sea fishing and fresh water angling are available in the locality.

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