help plzzzzzzzzzzz guppy is dying

Question
well i have two tanks 1 is a 40 gallon tank which i will upgrade to a 55 or 75 still thinking it has 6 angel fish some the size of a quater and others a little smaller i also have 3 baby clown loachs and 1 diano the 40 gallon tank has been setup for 2 years the diano is almost a year old and the other fish have been just find in that tank for 5 months it has a pump and a heater and 2 filters 1 whisper for 40 gallons and 1 new aqua clar 50!!! now my other tank which is a 10 gallon 1 has been setup for 2 months enough time to put fishes now so like we went to go buy 5 guppies from petland fancy guppies we had them for 3 weeks with out no problem the tank has a heater for 10 gallon tank and the filter that came with the 10 gallon kit but today 1 of the female guppies {which we bought 4 female and 1 male} was swiming upside down it wasnt dead because it was still swiming but it looked real weak swiming slow up side down {head first} all the other guppies are ok swiming just find i feed them 2 times a day !!! in the morning and night !!!
i dont know what the problem is !!! I really dont want my guppy to died !!! i want to know whats causing the problem and if my other guppies might start dying and want can i do to safe the guppy !!! Right now i took out the up side down guppy and put it in the bag that it came in which i always keep everytime i buy my fish . Well i put her in there with water from her tank and some water from the 40 gallon tank and than place her inside the 40 gallon tank iam thinking for putting her in there for now ontill she gets better but idk if i should ??? I think the problem might be is that i dont have a pump in the ten gallon tank and fishes need air so iam thinking i should put the guppy in the 40 gallon which does till i buy a pump tomorrow !! but i want to know if thats a good idea i dont know what to do and sorry for writing to much hope you can understand !!!! thanks for everything hope to here from you soon

Answer
Hi Rosa,
  You should have an airpump going in every fish tank.  As you say, fishes need air.  That said, I would not put a sick fish into the larger tank -- if it has a disease, that might spread to the fishes in the larger tank.   Your best bet would be to put the sick fish in a large bowl with water from the 40 gallon tank.  The bowl will have a lot of surface area and that should allow enough air to absorb into the water for one fish.

-- Ron
  rcoleman@cichlidresearch.com
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