Refraction. Take a clear glass, pour some water in it, and put in the glass a pencil. It looks like the pencil breaks.
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You will see what look like very small fish with tails (or possibly legs if they are becoming frogs soon) and frogs around your pool. If there are tadpoles in your pool you should be able to see them.
If you are looking for information on were can you find information on swimming pool designs, the best place to look is on www.dalpino.com
Improper water chemistry - stay out of the pool until they learn how to properly maintain a swimming pool. Last measure would be to test the water yourself for proper chemistry.
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Your face, in a swimming pool
With either a skimming net or get an effective floating pool skimmer
'Swimming Pool', sometimes shortened to 'Pool'.
Injuries to the head, hands, wrists and arms...Sometimes legs if attempting a backstroke tumble-turn or even a backstroke to breastroke turn. It was only today i injured my finger doing one of these turns; but these are the main fears of swimming backstroke in a swimming pool...
Is it an indoor pool or outdoor pool? Have a qualified swimming pool tech, a swimming pool inspector or a swimming pool consultant advise you through an inspection of your pool. They will find and actually visually see things that stand out as needing attention or repairs or adjustments. Those things I cannot do over the internet. k
it depends on which swimming pool
What are swimming pool "Coopers"