Selecting Fish & Avoiding Overpopulation

Pond life

Shimmering gold cuts through water, reflecting the early afternoon sunlight in short bursts of movement. Patterned scales are living art in a larger organic frame of earth and rock and textures of green that reach and spread in a range of hues and the occasional blossom. The scene is a Mother Nature original.

If only it was that simple. This scene requires the work of a devoted caretaker - one with a broader respect for the tenuous balance of an underwater environment and its inhabitants. Healthy fish are contributors to the larger ecosystem of a pond - care should be taken to make the proper choice.

Introduce any new fish into a pond already home to others, and the situation is delicate. Those already in residence have, for all intents and purposes, been in a sort of quarantine. Poor vetting of new fish can quickly wreak havoc, so carefully weigh any new additions.

Purchasing koi or goldfish directly from a fish breeder does have advantages. This option will reduce the number of “owners” the fish will have and fewer tanks it will call home. If there are no breeders in the area, online breeders will ship directly. While the convenience may be appreciated, koi shipped through the mail can quickly become stressed from the trip.

Another option is to buy from an area fish dealer where a buyer can view koi within a larger group dynamic before purchase. Know what to look out for. Fish should be aligned vertically - those that shift side to side or front to back should be avoided. If the fish is moving in a jerky motion it could suffer from a skeletal malformation - if it rubs against the tank, beware of hidden parasites. When fish swim at an unnaturally fast or slow pace disease might be indicated. If koi are gasping for air at the surface level, this could indicate poor water quality and an unfortunate sign about the fish dealer.

If you identify a specific fish you may want to purchase, request it be placed in a separate tank for observation. Look for dropsy or pinecone scale - an infection - indicated by scales that puff out from the body. Give it a once over and check for eye abnormalities and good proportion. Due diligence prevents a potential disaster to your pond’s ecosystem.

But what if you’re not looking to add fish but rather to curb the challenges of overpopulation? First rule of thumb...try to avoid overpopulation -  altogether - and do not overstock. For planning purposes, consider the size, filter and location of your pond - and consult trusted experts on the number of fish to purchase from the start.

Fish grow and spawn at a fast pace. If your pond becomes overpopulated, there are a few options to consider. Area pet stores might be willing to take the fish - or even pay a small sum. Local zoos have also been known to accept fish, especially fry (babies). Regional koi rescues have enjoyed great success placing fish with new homes - even local pond or fish enthusiasts might be an option.

A pond brimming with life and beauty is certainly proof of the power of symbiosis - each element, working together, contributing to the underwater environment. But an ecosystem requires a commitment to adding hearty species, able to do their part - including healthy fish.