Goldfish destroyed water lilies

[redwine]

I've had a pond with goldfish (mostly comets) and water lilies for eight years. For most of that time the fish and the water lilies have co-existed happily. A year ago the fish began to shred the lily pads and some days we'd find large chunks of lily leaves floating on the surface.

This continued until there were very few intact lily pads remaining so in the spring I removed all the lilies and repotted them. They had extensive root systems – I have no idea how old they are as they were already here when we moved into the house – so I reduced the roots, replanted them, fed them and put them back in the pond.

Two of the lilies quickly made new growth but as soon as the new lily pads reached the surface they were again ripped apart by the fish. Now all the lilies are dead.

I'd like to replace the lilies but I'm reluctant to do so if the fish are going to destroy them again.

Does anyone have any clues as to why the fish would start to destroy the lilies? They don't seem to eat the plants – just rip large chunks from the pads.

Nothing else has changed in the pond. The water is still clear and the number of fish hasn't increased or decreased. Any help would be most appreciated.

The attached photo shows the pond when it still had lilies.

Alison

 

[DrDave]

It could be that the small pond and the now larger fish are competing for space. Do you have an aquarium that the larger fish could be put in as a long term test? You could put a few smaller ones in with the water lilies and see what happens.

 

[redwine]

Thanks, Dr Dave.

I don't have another pond or aquarium where I can put some of the larger fish but it could be that the fish are competing for limited space. Some of the fish are now about 30 cm long.

I'll see if I can find a new home for some of the larger fish.

Is there a rough guide for how many fish a pond will support?

Alison

 

[DrDave]

There is a lot of information out there on this. And as many experts???

My personal opinion is, if you have enough circulation, filtration and aeration, you can have quite a few in a small pond. I like to have 1 Koi per 100 gallons. I have had as many as 3 per 100 and never lost a fish. I rescue Koi, so after a large rescue, I have quite a load on my ponds until I can find homes for them.

 

[j.w]

Sometimes when my lily pads start to deteriorate I notice my goldfish actually eating the soft brown parts. They have never destroyed the nice green ones tho and some of my fish are 8 to 10 inches. I've got a 2500 gal pond tho and only 24 or so fish so they are not crowded at all. Most of them are smaller too. I'd say your fish are rebelling and letting you know that they would like a bigger place to play or they are gonna wreck the place just to spite you

 

[redwine]

Thanks DrDave & JW,

I'll look for a new home for some of the fish and try again next spring with some more lilies. I guess the only thing that has changed in the pond over the years is the size of some of the fish.

The large fish have always been large – I gave a home to fish that someone no longer wanted – but some of those fish had babies a few years ago and the babies are now about 4 inches long so that will have increased the competition in the pond.

Thanks again for all the help!

Cheers,
Alison

 

[addy1]

Maybe they all just became vegetarians..................

I agree with the two above, how much do you feed them? Maybe feed them more so they are not "hungry" enough to graze on your lilies. Might help

 

[marla]

I have large goldfish and lilies and have never had an issue, even my koi leave the plants alone...except in the spring. I know the fish are always curious on the arrival of new plants to the pond but only the koi will pull at the plants.
do you have snails on the bottom of the pads? or little bugs? that they may be after

 

[redwine]

Marla ... there used to be snails in the pond – red ramshorns I think – but I haven't noticed any recently. Perhaps they are staying at the bottom although they may have died. There is algae on the sides of the pond which leads me to believe the snails may have died.

Addy1 ... I think the fish are getting plenty of food.

I'll try adding some more lilies to the pond in spring. It is coming in to autumn now in Australia.

Thanks for all the suggestions.

 

[adavisus]

Snails lay spawn on the underside of the lilypads, fish delish... If you can put a mesh cage around the waterlilies, that may keep the ravening hordes from being tempted to rip at such stubborn morsels stuck to the undersides of the lilypads

Regards, andy

 

[redwine]

Thanks, Andy,

That may be why I now have no snails and no lilies!