What is going on with my Frogbit?

[lilirose]

My Limnobium laevigatum- Amazon Frogbit- has something weird going on. I can't get a really good pic because my phone camera won't let me get close without blurring, but I've done the best I can.



The problem is the little black specks. They can be rinsed off but they come back. They are small and hard, like bits of sand. They are not bugs- or if they are, they are legless bugs that don't move and can't be squished (I know the pic makes it look like they might have legs, but those are jpeg artifacts, they are not there IRL).

The problem is occurring across all except one of my tanks. In one tank I recently had a near-complete die-off of the frogbit- it all turned brown and melted, despite it having done well before, and the tank having almost no flow. On replacement, these spots have returned.

Any ideas?

 

[Sarpijk]

Τhey look like aphids! I used to have them on my frogbit as well.

 

[lilirose]

Τhey look like aphids! I used to have them on my frogbit as well.

Aphids are hard, granular, legless, and do not move?

 

[Sarpijk]

Not really, the pic is not clear unfortunately.

 

[lilirose]

Not really, the pic is not clear unfortunately.

That's why I went to some trouble to describe them in my original post- I don't own a better camera. Again, they are hard like grains of sand, cannot be squished, do not have legs, and do not move.

 

[Sarpijk]

Do you have any other plants emersed or planted in pots next to the tank? I used yo have a caterpillar camouflaged in a ficus and I would find it's droppings on the floor.

 

[lilirose]

Do you have any other plants emersed or planted in pots next to the tank? I used yo have a caterpillar camouflaged in a ficus and I would find it's droppings on the floor.

I have eight tanks in various parts of my living room. This is a problem in four, one is "clean", and the others have no frogbit in at all. The "clean" one has more pot plants next to it than any of the others do.

 

[john dory]

Snail eggs?

 

[lilirose]

Snail eggs?

I only keep nerites, which lay small white eggs on hardscape- have never seen a nerite on Frogbit.

 

[john dory]

Limpits?

 

[john dory]

Oops just realised it's the black specks we're looking at..not white

 

[lilirose]

Oops just realised it's the black specks we're looking at..not white

The whitish specks are actually bits of duckweed, which is also recently struggling in a couple of my tanks (this also has me baffled).

I've ordered a cheap macro lens for my phone, maybe I can get a closeup and figure this out.