Pictus sick help!!!

[VWpictus16vT]

I seen yesturday that three out of my four pictus catfish there barbels have curled up. I have been fighting a NO3 problem started doing water changes with RO water have changed 10 gallons every other day for about two weeks now. This morning I could finally get a good look at the fish but dont know what is going on. PH 6.8 to 7.0 Ammonia. Is 0 to 0.25 NO2 is 0 and NO3 is 20ppm.the tank is a 55 gallon

 

[VWpictus16vT]

Well the third photo sucks but I need to know what the yellow thing in on his/her side looks like its growing inside. Sorry for two post new to forum

 

[VWpictus16vT]

More pics if it helps

 

[HUKIT]

Gill and barbel curl is a result of deteriorating water conditions, I'd step up the daily water changes to at least 25-35% and skip the RO water as this removes healthy trace elements(unless your adding them back in).

I don't know what the the stock is but curing high nitrates is simple, cut back on stock, improve filtration, or change more water...it's that easy.

 

[VWpictus16vT]

Awesome thanks I didnt know about the RO needing minerals added back in should have done more research. Stocking is 16 fish 4 of each Angels, Pictus, Cory, Opaline Gourami's. I will go tomm and get the stuff I need for the RO water can't do water changes with tap water that's were my NO3 problem came from...I have a well and live around alot of farming fields. Thanks agian for the help HOPFULLY my fish will make it through this. Any other info will be great as well.

 

[VWpictus16vT]

Well I started adding Seachem Replenish to my RO water and add some to the tank when I got it...pictus's started looking better but lost two three days ago and lost another one last night. Guess I didn't get it back on track soon enough. Still have one more no barbel curl or any signs of being ill but deff. not doing well. Hopefully the last one makes it. Every one else in the tank is doing fine. Just an update.