How often to change carbon (25 gal lagoon)

[firmefatboy799]

I think my last chemipure bottle said every 3 months, I would maybe go 2-2 1/2

 

[Cole.mormon]

Same

 

[scabbedwings616]

Like others say it all depends. since your tanks only fish, if you are treating with meds and need them out would be one reason, clean the water a little for cloudiness. This helps with par as well but fowlr it’s not so important