Tumors?

[snowdan13]

My acara has some tumor like bulge along his back. Appeared seemingly overnight. 

7.4 ph, no ammonia or nitrites, nitrates are a little high at 40, gh 8, kh at 4. I'm doing a water change tomorrow. 

Any idea what this is? treatable?

I should add, it appears on both sides of the fin and he's pretty lethargic 

[TheSwissAquarist]

That is a tumour. Try treating it with Maracyn and/or Expel-P

[Colu]

Could be a cancerous growth or a  viral infection such as lymphocytis can cause growth's like this or it could be a fluid filled growth what I would do is a course of maracyn2 in food the active ingredient minocycline has proven effective at shrinking some types of lumps and add aquarium salt 1 table for 3 gallons that will help reduce any possible fluid buildup