pond fish

[maddiemostmerry]

We made a garden pond for around seven years ago.
It has two tench in it, one large one smallish. They have both been in it since the beginning and seem happy.
Where I have a problem is with goldfish.
They are not living as long as they should.
I only have a few goldfish as the pond has frogs and newts but would like to feel the fish had the best life possible.

Where can I be going wrong?
The pond is 22 inches deep. Is this too shallow for goldfish?
I seem to have a major blanket weed problem which I treat with Cloverleaf Blanket answer.
There is a raised patio(concrete slab) next to the pond. Could run off be a problem?
I suspect I overfeed. Two goldfish two tench. Do they really need a daily feed?
Pond is pumped and filtered

Any advice welcome.

Thank you

Yes, it's too shallow. Ponds should be at least 1 metre deep so that fish can shelter from cold weather and hide from predators. Are there any cats around or have you seen a heron? Goldfish being brightly coloured and hanging around the surface waiting to be fed are sitting ducks really. Lots of floating plants should help the goldfish hide and also help with the blanket weed by cutting out some of the sunlight. Water hyacinth is pretty and it'll use up a lot of nutrients because it spreads so quickly.

Run off from concrete slabs can be a major problem too, sending the pH sky-rocketing. If you don't have a test kit then an aquatic shop might be able to test the water for you- get them to write down what the level is though because some of them will just tell you it's fine or tell you it's not fine and that you need to spend loads of money to fix it.

They probably don't need feeding every day, in the summer there are usually loads of insects around for them to eat but overfeeding wouldn't be the first thing I'd worry about.

Tench get fairly large BTW, how big are they now?

Hope that helps a bit, let me know if you need to know anything else!

EauRouge, thank you very much for your reply. It's very helpful.

Pond is netted as I have cats and the local heron is very interested in it.

Pond has lots of plants, garden is south facing though, so will have a look for a a water hyacinth.

I think my problem is the run off, so I will get the water tested.

Hard to say how big the tench are, but I would guess the small one is around 7 inches and the larger one 10. I have had them for seven years but they looked quite mature when I got them.
Pond is around 6ft by 4ft.

Pond is quite close to the house so remains quite warm, we didn't need to turn the pump off during the bad winter weather.

Are tench less affected by water quality than goldfish?

The pond contains two tench, two goldfish, newts, tadpoles etc.

Thanks

Ooh, newts as well? Cool! There's nothing in my 'wildlife pond' but snails If you've got newts and tadpoles then the water quality may well be OK.

Goldfish these days are nowhere near as tough as they used to be so it could be due to that. They are bred for appearance first; tench are native fish as opposed to ornamental fish so they are a fair bit tougher. They can get to around 2 feet long but I expect it can vary. Yours may still be growing.

Thank you.

I guess it's very hard to tell how hardy goldfish are when you buy them.

My tench may have some growing to do! My large one has a massive mouth when he come to the surface to grab some food, I'm amazed at how much he gets in at once.
Also found a stag beetle in the pond the other week, think the poor thing had been picked up by a bird and dropped in. I left him on a rock hidden away at the back to recover, he seemed ok.

I also have a cold water aqaurium but have a much better survival rate with that

My neighbour has a fantastic pond which is teeming with fish and he rarely seems to have any problems. He has pump/filter but rarely does much to the pond. I think sometimes I spend too much time checking mine and maybe disturb it too much, fishing out weed, kamikaze snails etc.

Thanks again.