Strange bug eating all my plants!

[Tuckers]

Hi this is my first time posting on this forum so I’d like to say firstly thanks for allowing me on and hello all!!

what brings me to the forum is a strange bug that’s been eating all my pond plants, I mean they eat the whole thing and they are infesting all the plants, so far I’ve lost at least 20 water iris amount some other plants as well.
these are some pics I took today, they Are clear in colour with a small brown strip down the middle however once removed from the water they turn brown and die.
They only live Under the water.
I cleaned all my plants and planting area at the start of spring to try and stop them but no avail.
my plants are cable tied to a plastic grate and suspended in a shallow planting area so they filter the water for a koi pond.
Any ideas how I can get rid of them? Or at least identify them.
I had a look online and they look like a water louse or water hog however water hogs are brown where as these are clear?
they are about 8mm in length when fully grown.
Thank you

 

[Lisak1]

It may help to see what kind of damage they are doing to your plants - do you have any photos of the plants with damage? Are you finding these on the plants or just in the water?

 

[Tuckers]

It may help to see what kind of damage they are doing to your plants - do you have any photos of the plants with damage? Are you finding these on the plants or just in the water?

I’m only finding them under the water level if you take them out of the water they seem to die.
They are also in the nexus 220 filter but not very many I suspect it’s only what has managed to get dragged in from the main pond.
they seem to eat all of the roots first and then start to eat the main bulb itself from the inside out so naturally the leaves wither and die and they feed off that as well.
I’ve just taken these pictures now, one is the main vegi filter where all my plants are / was And the others are of a iris bulb I just pulled out for reference, if you look closely you will see quite a few running around it.

 

[poconojoe]

I doubt the "bug" pictured is the culprit that's eating your plants.
The name escapes me, but those are good creatures. They are a type of fresh water crustacean. They are in my pond too.
When I first found them, I posted on this forum and got some good answers. I'll try to find that thread...

 

[poconojoe]

Here's a discussion on what I think you have pictured:

What are these shrimp like creatures?

They are clear and tiny, maybe a 1/4" long, and look kind of like shrimp. They seem to want to ball up when disturbed. I've seen them on my submerged pump in the past. Just today I repotted a plant and a few were on the soil as I pulled the small pot out of the pond. I'll post a couple of...

www.gardenpondforum.com

 

[Tuckers]

I doubt the "bug" pictured is the culprit that's eating your plants.
The name escapes me, but those are good creatures. They are a type of fresh water crustacean. They are in my pond too.
When I first found them, I posted on this forum and got some good answers. I'll try to find that thread...

Please do find it if you can I’d be very interested to hear what people think,

all I can find online is that they are most certainly a water crustacean called asellus aquaticus as it’s the closest to anything I’ve found. It does say as you said it hat they are a friendly creature that cleans up the bottom so to speak however I did find this arrival
“Water lice are omnivorous scavengers, happily feeding on the flesh of dead fish and rotting plant matter. When decaying matter is not available, they feed on the shoots and leaves of fresh plants, much like their landlubbing cousin, the wood louse. Left unchecked, water lice without enough detritus to eat can cause extensive damage to a decorative pond. Water lice populations are controlled by pond fish and water spiders.“

there is absolutely no waste of any kind on the bottom of my ponds in the main pond or the veggie filter as I always clip the dying leaves so I can only assume they are eating what is available and that’s the roots and new shoots. There is no fish in the veggie filter but perhaps mabe I should put a couple of small growing fish to help clean up some of the numbers.
I have no issues with them being in the pond but my plants are almost non existent now. I check the leaves and there are no other bugs of any kind or even bite marks

 

[j.w]

@Tuckers
I think that bug may be a Scud: http://lifeinfreshwater.net/scuds-gammaridae/ or a Water Sow Bug: http://lifeinfreshwater.net/aquatic-sow-bugs-asellidae/

 

[Tuckers]

@j.w i think you may be right there, it looks very similar to both of them although I’d say the sow bug is the closest match apart from my bugs are clear with just the brown streak down the middle rather than being brown all over, the biggest one is at most 10mm most are shorter than that, I never see them swim either they are always attached to something.
many idea how to thin them out? I’ve already cleaned the whole veggie filter section out and hosed the plants down but they always creep back in no time.

 

[Mmathis]

Wow, talk about timing!

I am a big fan of scuds and their job in the pond ecosystem. But for the past few weeks I’ve noticed some nibbling on plants in my Skippy filter. I thought that was odd. Sooo....now thinking they aren’t scuds after all! Thanks, @j.w for pointing out the differences in the scuds and their look-alike!

 

[j.w]

According to this article you don't need to get rid of them as they eat decaying plant material. It does say seeing them in a steam is an indication of lowered water quality:https://nature.mdc.mo.gov/discover-nature/field-guide/aquatic-pillbugs-and-sowbugs-aquatic-isopods
Also says: Freshwater isopods are important scavengers, contributing to the decomposition of plant and animal remains and helping clean the water. They are also a favorite food of fish and many other aquatic predators.
Your koi will eat them if they can get at them.

 

[IPA]

Please do find it if you can I’d be very interested to hear what people think,

all I can find online is that they are most certainly a water crustacean called asellus aquaticus as it’s the closest to anything I’ve found. It does say as you said it hat they are a friendly creature that cleans up the bottom so to speak however I did find this arrival
“Water lice are omnivorous scavengers, happily feeding on the flesh of dead fish and rotting plant matter. When decaying matter is not available, they feed on the shoots and leaves of fresh plants, much like their landlubbing cousin, the wood louse. Left unchecked, water lice without enough detritus to eat can cause extensive damage to a decorative pond. Water lice populations are controlled by pond fish and water spiders.“

there is absolutely no waste of any kind on the bottom of my ponds in the main pond or the veggie filter as I always clip the dying leaves so I can only assume they are eating what is available and that’s the roots and new shoots. There is no fish in the veggie filter but perhaps mabe I should put a couple of small growing fish to help clean up some of the numbers.
I have no issues with them being in the pond but my plants are almost non existent now. I check the leaves and there are no other bugs of any kind or even bite marks

How big is you pond? What you say makes sense that their population is unchecked and devouring the plant roots seems logical. Depending on size of your pond maybe a couple minnows or goldfish?

 

[Tuckers]

@j.w
That article also says that they will eat living plants as well, it does sound like them but there is no plant matter in the planting area so I’m not sure what they would have been living off to grow such numbers if they eat decaying matter.
My koi can’t get into the planting area as it’s completely separate, the only way they will get them is if they get washed over the waterfall then it’s fast food all round.
I’m considering putting a couple of fish in the plant area so they can munch on them, problem is the fish waste would them likely build up as it’s bottom entry and overflowed back into the pond.

 

[Lisak1]

It looks like your irises have borers. Do the roots feel mushy? Are the leaves dying from the top down? Sometimes borer damage will leave a terrible stink when you pull up the dead leaves or roots.

 

[Tuckers]

How big is you pond? What you say makes sense that their population is unchecked and devouring the plant roots seems logical. Depending on size of your pond maybe a couple minnows or goldfish?

The main pond is 4m long 1.5m wide and deep.
Planting area is 1.5m long by 1m wide and around 500mm deep.
during the winter month I open up a run off pipe that’s about 3” down from water level in 44mm pipe to stop the waterfall running, I’d have to put a cover over I suppose to stopwhat ever fish I put in there from getting sucked to the main pond

 

[Tuckers]

It looks like your irises have borers. Do the roots feel mushy? Are the leaves dying from the top down? Sometimes borer damage will leave a terrible stink when you pull up the dead leaves or roots.

The roots on the bulbs with no leaves are mushy but I suspect that because the plant is now dead, I leave them in a while just incase it is just dormant from having been eating so to speak.
the leaves do die from the top down they turn brown at the tips. I have cut off the tips a few inches down into the green and I’ve never noticed any internal damage to the leaves? Also my plants are not in soil they are suspended and tied to plastic grating. I’ve never noticed a bad smell but I haven’t really been checking for that and also am didn’t want my face to near a bulb crawling with critters haha. I will check tho tomorrow. I haven’t seen any moths around but then that would only be at night I suppose, I do check the outside of the leaves regularly to see for black aphids but I’ve never seen anything on the leaves at all.