New plant,Fish dying :(

[Nikki_mc]

Hi,

Newbie here, that might be quite obvious...

We have had our outdoor pond now for about 1.5 years. It is about 2m x 1m, has a filter and water is circulated well around the pond. The goldfish have been going well and strong. But as of 3 weeks ago I've started to lose a fish a week I am quite devastated. The only thing we have changed is I purchased a water lilly for it. Week later first fish died. Third today. Could the plant be toxic? It was in a pond at the store that had a few fish in it. But not gold fish.

Please help. I only have 3 left and I am quite fond of them.

 

[JamieB]

The things everyone will want to know is have you tested the water, what kind of filtration you have, and any airation? What kind of plant is it? I’d say pull it, put it in a bucket of water, test your water, get an airstone going if you don’t have one. If you have pics of dead fish, post them. The others know a lot more, I’m new, but being a night owl here in the US, I’m up late, so I can tell you the info they will need, and some basic advice.

 

[JamieB]

Since you say you have filtration and good movement, I’d check the fish for any parasites, did you quarantine the plant? Washing it in a dilution of bleach water for about 10 min I think is what’s recommended, I’m sure the others will pitch in. Plants can have fish parasites on them, most of us who don’t know better would just plop it in the pond. But I learned everything gets quarantined, I lost over half my fish from that lesson.

 

[Nikki_mc]

I removed the plant this afternoon, I dont know what kind of Lilly it is. It has small leaves not the big frog sitting on type ones lol Dead Fish have all looked fine. No spots or funky scales/fins. Eyes clear etc.
I am not sure how to answer the other questions. I dont know enough about filters to tell you the kind. I know its a large one, about the size of an A4 paper. Has two boxes with white rock in it and a filter thingy. I have it so the water bumbles on top and keeps it moving. The waters crystal clear and very little algae. I have not tested it,ever (probably why I have dying fish). I will buy a kit tomorrow and do so.

 

[JamieB]

The white rocks sound like biological filtration. If you loose another fish, snap pics, once you test, post results. The pond tester kits cover more than aquarium test kits, so if you can, get one of those. All I can think of is low oxygen in the water, and as plants create oxygen with sunlight, they use it at night, so maybe it depleted enough that fish died. Was it the bigger ones? Look your fish over carefully, alive and dead. See if there are changes in how they are acting, changes in looks, etc.

 

[brokensword]

Do your fish show any symptoms? Always at the surface gasping for air, always on the bottom hardly moving? Are they flashing against rocks, etc?

What is the weather like there (winter,spring, etc air temps).

What gallonage do you have (you only give LxW; need depth too).

Get the liquid type API water test kit. If you're high in ammonia, nitrite or even nitrate, that will affect water quality and the fish will suffer (but you should see symptoms as already noted).

Water source? (as in, city water, well water, rain water; these are prob okay as you say your fish have been fine for over a year now)

Any recent sprayings of fertilizer/pesticide in and or around the pond?

Any water addition without adding dechlor?

The lily probably isn't the culprit but as Jamie notes, might have brought in a bug. From your description of the fish, I'm doubting the plant is the problem.

You haven't added any 'additives' lately, have you?

Changed water in large proportions?

How much organic matter is decaying at the bottom of your pond?

How often/have you cleaned the filter (lately, routinely, etc)?

How much are you feeding them? (again, knowing what season and zone you're in would help).

How many fish and approx what size?

Aeration and or water movement? Sounds like you have the latter but hard to say how much from your description.

Can you post a pic of your setup? Goldfish are really hardy, so I'm betting something is off re your water parameters.