So I have one fish in my entire tank that is showing an issue. One otocinclus catfish (out of five) has a white,fuzzy patch on his nose that appears to be growing, but quite slowly. Otherwise fish does not appear ill nor is he acting ill. Still eating as far as I can tell. I was thinking a salt treatment but I'm not sure in what concentration, otos being finicky about changing water conditions. No other fish in the tank appear to be affected; I just checked all the other otos and they look fine.
1. Size of tank? 29 gal high
2. Water parameters
Ammonia, nitrate and nitrite all test at 0 (on test strips, do not have a numeric tester)
d. pH is ~ 7.8, hardness - quite hard, do not have a numeric tester but local Petsmart says tapwater tests around 300.
3. Temperature? 78 - 79 deg (monitored several times daily)
4. FW (fresh water) or BW (brackish)? Freshwater
5. How long the aquarium has been set up? Seven months. Otos were added 6 mos ago.
6. What fish do you have? How many are in your tank? How big are they? How long have you had them?
5 otos, 3 plays, 2 honey gourami, 4 white clouds, 2 endlers. All roughly adult size except for honeys, which are still adolescents.
7. Were the fish placed under quarantine period (minus the first batch from the point wherein the tank is ready to accommodate the inhabitants)? No quarantine as I do not have a quarantine tank. Honeys were added 1 mos ago, no symptoms on those fish. First noticed fuzz on 1 oto about 1 week ago. Endlers were added two days ago. All other fish have been in the tank for several months.
8. a. Any live plants? Fake plants? Fake plants, yes. "silk" type. Otos spend most of their time here. Live plants - floating frogbit
b. Sand, gravel, barebottom? Gravel bottom
c. Rocks, woods, fancy decors? Any hollow decors? Rocks and a bubbler. Nothing hollow.
9. a. Filtration? AquaClear 50
b. Heater? Normally yes, but it is 110 degrees outside and we are using A/C just to stay at 78 in the house, so the heater is unplugged!
10. a. Lighting schedule? What lights are used? Standard fluroescent hood lamp, lights on from ~6:30 am to ~8 pm.
b. Any sunlight exposure? How long? No natural sunlight.
11. a. Water change schedule?
b. Volume of water changed? About 4 gallons each, 2x a week
c. Well water, tap water, RO water? Tap water
d. Water conditioner used? No, treated for chlorine
e. Frequency of gravel/sand (if any) vacuumed? During each water change
12. Foods? Tank gets flake but otos don't eat that. Algae in tank supplemented by zucchini, lettuce, algae tabs. Zucchini and lettuce are routinely blanched/boiled then cooled before being added to tank.
How often are they fed? I add fresh veggies about twice a week.
13. a. Any abnormal signs/symptoms?
b. Appearance of poop? Not that I've noticed
c. Appearance of gills? Not that I've noticed
14. a. Have you treated your fish ahead of diagnosis? No