Wednesday, September 30, 2009

Fish are cannibals

I get questions at my website and occasionally share them here.  Here's one that you may not know or have forgotten:


I have goldfish.

So, do the alive fish eat their dead? I've actually never seen a fish eaten like this is my pond. Sure, I have found plenty over the years, in all seasons, die and float to the surface, but never eaten like this.

I will take your advice and resist the temptation to feed them even in this warm spell.


Yes, all fish will eat other fish. In fact, fish will kill a sick or weak fish. I think it is a way they have of keeping the school hardy.

Your goldfish will be just fine if you never ever, feed them, even in the summer. Just balance the pond ecologically with submerged vegetation and make sure your bioload is not too high and you can just relax and never have to clean fish poop out of your pond except in your yearly cleaning.

Saturday, September 26, 2009

More about irises

I forgot to mention yesterday that it's time to cut back irises.  Many people do it in the early summer right after the plants bloom, but I like to enjoy the foliage all summer, so I wait until fall to cut them back.  Remember the iris blooms on new growth, so divide and cut back. That way all growth next spring will be new and you will irises to share and irises to enjoy.

Wednesday, September 23, 2009

Pond liner problems

I have a website at
People ask and answer pond questions there. Occasionally I get an common question and share it here. Here's one about liner suddenly rising from its floor:


We have an in ground, 8' fish pond that was built 4 years ago. We buried an 8' stock tank and laid the pond liner over that and put about a billion rocks around it. This year, water has started getting between the stock tank and pond liner and rising the liner up out of the pond. A recent 5 " rain really has brought the issue to a crisis point. I see no obvious leak in the liner and we really don't want to move all those rocks to lay in a new liner...what should we do? We have pumped it out a couple times, but water keeps getting between the liner and stock tank.

You have methane between the tank and the liner. No amount of rocks will keep it from rising. Try to make a place where you can pump out the water that has gotten between the two. That will help until it happens again. The only way to stop it from happening is to raise the entire pond, tank and all. (Shudder.) Or you could build up the sides, make the pond bigger and use the weight of the water to keep the liner in place, but if you do that, you might as well just start over with just a liner and no stock tank. You have a big job ahead of you.

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