PlanetCatfish.com

I cannot remember the name of this guy, but supposedly they only get a few inches. it was something like a timinikki pleco.

1. Water parameters
a) Temperature range. 75
b) pH. 7.4
c) GH. unknown d) KH. 4-5
e)Ammonia, Nitrate, Nitrite, levels. ammo:0 nitrite:0 nitrate: <20
f) Water change frequency: 50% weekly
(Most LFS's will check your water and give a list of readings).

2. Tank set up
a) Size. 20 gallon long
b) Substrate. very fine sand(for cories)
c) Filtration. fluval u3 and fluval u2
d) Furnishings. driftwood.
e) Other tank mates. 5 cories,6 bloodfin tetras, 5 rummy nose tetras, 1 dwarf gourami and t2 kuhli loaches.
f) How long has it been set-up? 4-5 months.
g) When was the last new fish added? 5 rummy nose tetras.
h) Foods used and frequency? algae wafers and other bottom feeding fish food.

3. Symptoms / Problem description: started as a little white spot and has grown over a couple weeks to mor eof an indent with a little red coloration around the white indent.(like something is eating it's flesh)

4. Action taken (if any) just water changes.

5. Medications used (if any) none

Could it be a heater burn??

It looks like heater burn to me as well, try moving the heater and then make sure there is someplace for the fish to hide other than behind the heater.
There are heater protectors available as well that will keep fish away from the hot section.

Birger

I suppose it could be heater burn, i have never seen him by the heater but they are sneaky.