Please Help A Newbie, Guppy Problem

[Gillette1985]

i woke up this morning to find my guppy sat upright, pointing to the top of the tank. I thought it was dead. After grabbing my net, and giving him a little nudge he started to swim around, always ending upright once he stopped. I've done a water test thinking it may be that thats the problem.

Cl 0.8
P
Kh 6
Gh 16
NO2 0
NO3 0

Could someone please tell me if they may be the cause?? Just in case i've done a 20% water change only about 15 mins ago. I've been watching my guppy now, and he seems to be hanging around on the gravel, almost sitting on it with very little movement. My worry is that the neons will start to attack him if they see a weakness. I dont have another tank to use as a hospital, so unable to remove him.
Please help!!

 

[Noahs ark6]

The only thing i can think of is swim bladder if so you will just have to leave it or kill him. good luck

 

[Gillette1985]

guppy got worse as today has gone on, very little movement. been down my local maidenhead aquatics to talk with them, the worker there didnt think it was swim bladder but an internal bacteria problem. so armed with the correct treatment, and some of that aquatic salt, i come home to find him dead

 

[WILDER]

How many gallons or litres is the tank.
How many fish and which type.
What the make of the test kit you are using.
Do you have ammonia reading please.

What does it look like when the fish goes to the toilet.
Is the anus enlarged or red and inflamed.
What do you feed the fish.
Are scales sticking out.

Don't feed for a few days.
Feed some shelled peas.