help for my guppies

[ruffmeister]

noticed today one of my male guppies seems to be swimming vertically, and also has 2 red spots on his tail which where not there before( he is a yellow fish) anybody know what this is, I have done nitrate and ammonia checks to see if this was the cause with the following results
ammonia - none
Nitrate - 15 - 20
which to me seems fine. They have been in the tank 1 week with no other problems. concerned about my poor little fish PLEASE HELP!!!!!

 

[guppymonkey]

Nitrate - 15 - 20

Is that parts per million or mg/l? It seems a bit high (not that I really know that much). Did you cycle the tank before the fish went in? I made the mistake of not knowing to cycle the tank and watched one of my platies go from swimming fine one minute to lying on the bottom and dying. Sorry I can't really help maybe someone who knows more can give you a hand.

 

[ruffmeister]

its per mg/l

the reccommended it 40 so it low could that be a problem, as for the tanks yes it was fine and as i said they have been fine for a week