Flashing: Parasites or Aggression Display?

[fishman888888]

125 gallon community tank
Ammonia: 0
Nitrite: 0
Nitrate 5-10ppm
Kh: 20
Gh: 60
Ph: 7.2

Tanks been cycled and healthy for a year

4 leopard ctenopomas
1 black angel
5 blue gouramis
9 bosemani rainbows (6 f, 3 m)

The issue is with the blue gouramis only.... they are the only fish in the tank that flash.
They only flash on my heater....
Ive had them for a month and theyve been flashing for 3 weeks...
No other fish in the tank flash

I treated the tank with api general cure as a precaution, cause all signs point to parasites...

They seemed to have stopped for a few days, but theyre back to it.

Ive read that gouramis can flash as a display of dominance for one another...and i do have 5...is that probly too many?

Any ideas/experience is appreciated, thanks guus

 

[Istrom]

It's a disease or parasite, maybe Ick.

 

[fishman888888]

It's a disease or parasite, maybe Ick.

Yea i know.... they're not bloated, and they all eat a ton... i dont have any symptoms to go on...except 1 type of fish, flashing on one object...

I keep my water clean. 2 x 50% water changes a week.

What could i try? Salt bath?

 

[Istrom]

Well that's an option, but most people tend to turn the temperature up to 86 for about a week or two.

 

[fishman888888]

Would that do anything to treat parasites? It might not be ick... i suppose its worth a try though

Another detail - after they flash their colouration is extremely bright, equivalent to when they fight for territories when i rearrange things in the tank.

 

[Istrom]

The only thing I could guess is either they are for some reason re establishing a slime coat and have to remove the old one first, or dead cells need to be removed.

 

[fishman888888]

Do you know anything about planaria? ...
Could they make fish flash?

 

[Istrom]

It MIGHT be chlorine poisoning. When was your last WC and did you use prime?

 

[fishman888888]

Definitely not chlorine poisoning

What about planaria

...theres what i originally thought to be algae growing on the glass... never seen it before

 

[Istrom]

Nope, planaria are not parasitic.

 

[fishman888888]

Doesnt it cause excessive slime coats? Maybe theyre just uncomfortable cause of that

 

[Istrom]

Hmm... That could be it. Go to your lps about solutions though.

 

[fishman888888]

K, it is in fact algae lol

So....parasites are back to my prime suspect

What are the best meds?

 

[Istrom]

Heat honestly. It puts a risk on your fish but it will kill almost all viruses and parasites.