koi disease & Fish Death through scraping Brick Pond Sides

I built my pond with a ledge on the inside for plants but unfortunately the ledge is 2ft below the surface, which is fine for lilies but not suitable for plants that like just 6in of water. I made the mistake of using bricks to build up the ledge and one of my Koi has already died from an infection caused by rubbing against the brick. I cannot find a safe alternative, can you suggest anything? JD Heather, Lincs

To JD Heather

It would be possible to wrap the bricks in black plastic or underlay material. Alternatively support the planting baskets on baskets or smooth plastic containers filled with inert gravel. My feeling is however that the fish had an irritating infection first and were using the bricks as a 'backscratcher'. Their immune system would have been very low and their mucous layer would have been very thin making them very prone to parasites. Also if your water has a high pH this also can make the fish very itchy.

Perhaps you should be looking for constitutional treatment and a good vitamin supplement that will help them get over the traumas of the winter.

Treat any freshly added water from the mains with pool conditioner. Pool condioners remove chlorine and chloramins that are put into drinking water to kill bacteria and other undesirable.