Sick male green cobra guppy

Question
We've had our male green cobra guppy for about a month and a half.  He was very active, playing with the other fish all over the tank.  About 5 days ago he was hanging out at the bottom of our tank, laying upright on the gravel, breathing rapidly.  We have a 10 gallon tank, ph is 8 (I know it's high but it's been that way from the beginning, we can't seem to keep it lowered), the amonia is at zero(we had problems with our amonia before and finally got that down), and we do a 25% water change once a week, give or take a day.  We also bought a new air pump to increase the oxygen.  The filter pad gets changed every 3 weeks or so and it's washed off first in the old tank water before being put in the filter.   He eats at the top and then goes back down to the bottom.  He's starting to pale in color on his body and his tail is fading a bit.  The other fish nudge him once in a while and he runs away and hides.  His belly isn't bloated and his scales are not sticking out so I know he doesn't have dropsy.  We've tried looking up the answers ourselves but have come up with nothing.  There are 4 other fish in our tank, a blue dwarf gourami, a marble molly, a cherry barb, and another male guppy so we don't want to put in any chemicals unless it's necesary.  We do not have a seperate tank to put him in, we just have him quartered off in a breeding box so the other fish don't hassle him, we didn't put him in there until tonight so I don't know if he's pooping, we'll see tomorrow.  None of his symptoms match any of the deseases we've been reading and are hoping it's not a parasite.  We are going to try giving him mashed peas to eat tomorrow in case he's constipated but would that make him lose color?  All of the other fish are fine and show no symptoms of this at all.  We feed them a mixture of flakes and blood worms.  The tank light is on for about 12-14 hours a day while we are at work.  Any advice would be greatly appreciated.

Answer
Hi Jill

Resting on the bottom of the tank is a sign of constipation which can also lead to a more serious condition, Swim Bladder Disease.

Some remedies I've read suggest treating with 1tsp of Epsom Salt to relieve the stress and internal pressure. I would start by feeding him the pea in the morning and don't feed him again for a couple of days. Be sure to feed him small enough portions for him to eat and not too much at once. And yes, any type of ailment including constipation can cause a loss of color. I know it makes me lose my color (among other things :-/)

Once you notice he's pooped, he should be on the road to recovery. If not, there is something else going on, quite possibly an internal infection or Swim Bladder Disease. At which time you may need to treat him with Pimafix or an antibiotic such as Maracyn.

Tetramin Tropical Flakes should provide your fish with a well balanced diet. Keep in mind, adult fish only need to be fed once a day. Bloodworms should only be offered once a week as a treat, not as a standard part of their diet.

Hope this helps you and he gets better soon! Good luck!

Richard