Our little fish pond

Rose likes to keep fish and breed them.  One female Swordtail has recently given birth to more than 80 babies. I am amazed at the number she manages to keep in her body, she is about two inches long and the babies are about 1/6 inch long.  How are the babies fed in her womb, I wonder?

The fish normally live in our pond which is a little less than two metres square, but when a female looks pregnant and might be about to deliver, She is put in a tank, then when she has finished delivering her fry, she is returned to the pond and not kept with the fry because parents sometimes like to eat their children.  The fry will be transferred to the pond when they are big enough not to be eaten - perhaps 3/4 inch long.

Th pond itself is one foot deep at one side, sloping to two feet at the other.  There are three water lily plants (they multiply) and a large quantity of Acharis, a fast-growing plant that can choke up the whole pond and has to be severely pruned from time to time to give the fish room to swim and us the possibility of observing them.