Lates. C parasite?

[mjohns]

Hi all, ive been having a problem with my lates not long after i got him really (a month or more), he has no visible signs of injury or parasites, looks to be in good health. Maybe sometimes has a slighly lighter color, snaps his mouth rarely but yawns every now and then, sometimes flicks, rubs himself against things (including other fish). Still eats like an absolute pig no problem there.

Im thinking it must be a parasite of some kind, possibly internal? I have tried to treat with "para-gone" (trichlorfon 20mg). This is the only parasitic medication i have found.

My other fish all seem fine and dont show signs of any problem though i bet it wont take long.

Thanks alot.

http://www.monsterfishkeepers.com/forums/editpost.php?do=editpost&p=2626635

 

[mjohns]

just tested my water..
Ammonia - extremely high around 4.0 :| EDIT: Tested tap water 0 ammonia
Nitrite- 0.25
High range PH- 7.4(lowest)
PH - approx 6.4 (should maybe be a bit higher??
I find this extremely hard to beleive, maybe my ammonia test solution is no good? Im running a 2400 canister, a 1400 sponge type filter and a decent size sump. Tank is a 6x2x2.5 containing 1 ~35+cm salmon tail
1 ~35cm barra
1 ~ 40+cm clown knife
1 ~ 45+cm catfish similar to rtc
1 ~ 20cm peacock bass which i just got

I cant beleive it.. Where do i start now..

Filters are pretty full with an assortment of media , sponge, lots of ceramic rings, bio balls, that gravel type stuff etc.
I guess ill stop feeding might do a decent w/c again (did one yesterday)

This sucks though my other fish seem fine?

Tank isnt clear as and i just stupidly cleaned my canister which im now regretting. I didnt touch the bio media at all but who knows.
What should i do?? a decent water change even though i cleaned my filters today or maybe wait and test tomorow?