Kuhli loach illness, help with identification/treatment

[kjc]

Hello, I have a kulhi loach with what appears to be a tumor on his head, not sure if this is a treatable affliction. Fairly new at fish keeping and would like some assistance with identification and possible treatments. I noted this tumor of sorts just recently. My loach is a grey/pink coloration(normally), has appeared normal, he/she is very shy and does not come out into view much. I saw him/her about 12 days ago and it appeared fine and was eating. Had not seen him until yesterday evening and it has a fairly large white/orange tinged growth in it's head, also has patches of skin discoloration that were not present before (not a film just a few patches of lighter pigment on its sides). Behavior is normal and it is eating as far as I can tell.

fish type; kulhi loach
tank set up; August 8, 2012
tank size/dim; 27 gallon tank, 24 in wide x 17 in heigh x 10.5 in deep bow front
tank filter: Fluval 204
water temp: 78 degrees
Tank maintenance: water change between 8 to 14 days 25%, trim up plants if needed and add 2 teaspoons total of tetraplant floraPride no other additives we have good well water.
Tank changes: Last addition to tank was on Nov 18, 2012 of one small otocinclus, in the last month and half I have had an algae explosion for unknown reasons and I had a snail
Tank inhabitants: planted tank with large bog wood piece, natural rocks with 1/2 sand and gravel substrate, 1 platy, 1 red eyed tetra (both about 2 to 2.25 inches long), 2 otocinclus, 1 male powder blue dwarf Gourami and 2 kuhli loaches. Everyone looks and acts very happy and healthy and gets along well. Around 6 or 7 snails (came in on the plants) I take them out to keep the numbers to that level. I have a C02 system set up that bubbles into the intake so the impeller incorporates it into the water.
Current water parameters; Use freshwater master test kit for levels
Nh3 0ppm
N03 20ppm
N02 0ppm
GH 15ppm
Alk 240ppm
pH 7.6
any ideas how I can help this guy out. Really like these guys. Picture included. Thank you.

[Diana]

That is a very large growth to have happened in just 12 days.

I can suggest a few things, but do more research before deciding on anything.
1) Google Lymphocystis. It is usually MUCH slower growing.
2) Tumor or some similar growth: Not much can be done. In a place as important as the head you probably will want to euthanize the fish. It is growing so fast, and will be interfering with eating and breathing. Look up Clove Oil.
3) I do not think it is an injury or disease or parasite. Even in softer tissue, with the inner tissue pushing outward, I have not seen an injury like that.