koi fish

A koi pond is one of the most dramatic and memorable additions you can make to your yard. While caring for koi can be a meditative experience, sometimes real issues come along that can impact their health. Knowing how to spot and correct these problems can keep your costs low and your fish healthy for years to come.

1. Waste Products

Polluted water can quickly make your sick or worse. The waste products from your own fish are one of the biggest causes of koi pond water contamination, because the ammonia buildup can burn their gills.

There are chemicals you can use in the short term to lower the ammonia levels, but in the long term you’ll want to check out your filtration and bacteria levels.

2. pH Levels

Extreme pH levels are a close second behind ammonia and nitrate buildups. 7.0 to 7.5 pH is ideal for koi, though anything from 6.7 to 8.3 shouldn’t be a big problem. pH levels can and do change daily, so don’t be too worried unless they become extreme.

Be sure to regularly test your water’s pH levels and correct them as necessary.

3. Bacteria

Parasites can wreak havoc on your koi in no time at all. Stressed fish and injured fish are particularly vulnerable to bacterial infections, but even otherwise healthy fish can fall victim to them.

If this is an ongoing issue for your fish, consider upgrading to a better filtration system and incorporating a UV sterilizer.

4. Overcrowding

One of the easiest mistakes to make with a koi pond is to simply fill it with too many fish. An overcrowded koi pond will produce more waste products, consume more oxygen, and stress your fish out. Furthermore, koi in overcrowded conditions will release a hormone that stunts their growth, giving you smaller koi.

The good news is that the solution to this issue is really easy: just buy less koi, or give some away to your friends. Also be sure to cull your fry if some lay eggs.

5. Local Pests

New koi pond owners often don’t know what to do about the birds, cats, raccoons, and other critters that prey on fish.

Netting the surface of your pond is one option, though it can take away from the look of your pond. A better option is to design your pond so the predators won’t have anywhere to stand. Make sure that the drop from the edge to the surface is too deep for predators to stand on the edge and reach down. Deeper water can also give you fish a place to hide in the event of a predator.

This post was brought to you by Chuck’s Landscaping in Canoga Park, California, specializing in waterfall installation and pond construction throughout the Los Angeles Area.