Earlier on today I received an e-mail from a neighbour down the street asking if I could come and take a look at the fish in their pond.

Upon arrival I found the problem: several of the fish (three Koi and four Golden Orfe) were covered in fungus. One specimen was particularly bad and had to be euthanized as the fungus had turned to finrot which had badly damaged the skin around the caudal peduncle (where the caudal fin joins the rest of the body) and had also somehow spread into the gills.

The other fish are currently in quarantine. I pin-pointed the cause of the problem down to two things: poor water quality and the very low water temperature. Although aquatic diseases are somewhat dormant over the winter, fish metabolism is down and so are immune systems, it becomes very easy for fish to become infected if they're stressed. Poor water quality itself is a major cause of stress in fish.

If the pond owners (not that I'm blaming them) had tested the water frequently the entire issue could have been avoided.

I cannnot stress enough how important it is to test your water on a weekly basis. This means a full test for pH, ammonia, nitrite and nitrate. If you don't currently have a test kit then buy one now. Water quality problems can be picked up early and dealt with before other problems set in.

The same also applies to aquarium owners.

good advice

Never a truer word spoken. Best to use natural water cleanser too.

We use eco freindly stuff, theres a cloudy water treatment and a mud muncher treatment lol

worth mentioning. we get it from

https://www.wikaniko.com/wexec/order..._cat=31&page=1

Sorry, but I don't stand by so-called chemical 'tank cleaners' or 'water cleaners'. They're a complete waste of money and there is absolutely no scientific evidence or proof from fishkeepers to show they even work.

Water changes are the key to maintaining good water conditions.