Elysia Obtusa (lettuce) sea slugs

[Lyss]

I posted about this in the ID forum a bit ago but probably better to discuss here since I know what I have and would love to know if anyone has experience with or information about these slugs in captivity.

I noticed one last month and thought it looked cool. W/in a few weeks I began seeing them all over the rocks at night. They are 100% Elysia Obtusa, and I have one that’s about an inch long and looks EXACTLY like the photo here: http://seaslugs.free.fr/nudibranche/a_elysia_obtusa.htm

I see them out and very active all night into the early morning — there is at least one bigger one, and many baby-sized ones. Between them and my pitho crab the macroalgae-gone-wild problem I’ve had in my display is vanishing, so they seem to be useful as well as cool.

I just wondered if anyone knows anything about them in captivity. They seem to be thriving and multiplying in my tank, which is surprising.

 

[CK00020]

How much flow will they tolerate?

 

[Lyss]

How much flow will they tolerate?

They seem to not care too much — I see them at the back of the tank up where the flow is very high, as well as the front of the tank and lower on the rocks where the flow is more gentle.

 

[CK00020]

I will definitely get some with my next cuc order. My last order had some in it but they were doa

 

[Spare time]

As with most nudibranches and sea slugs, they are best avoided in the hobby due to extremely specific dietary requirements. These eat siphonalean algae, which I assume you have in the tank if they are reproducing. However, I probably wouldn't tell someone to buy them unless they know they have that algae. They appear to be extremely understudied so it's probably a lot of guess work when trying to keep them in captivity

Elysia obtusa | Jeffrey Ikin

 

[CK00020]

I have some areas of bryopsis that I am looking to keep under control

 

[Lyss]

As with most nudibranches and sea slugs, they are best avoided in the hobby due to extremely specific dietary requirements. These eat siphonalean algae, which I assume you have in the tank if they are reproducing. However, I probably wouldn't tell someone to buy them unless they know they have that algae. They appear to be extremely understudied so it's probably a lot of guess work when trying to keep them in captivity

Elysia obtusa | Jeffrey Ikin

That's why I'm so surprised. I saw just one a few weeks ago and thought, "cool, well that won't last..." And now there are many.

I have lots of coralline on the rocks, and LOTS of ulva (which, honestly, is now disappearing but that could also be due to my pitho crab), and not any GHA or bryopsis that I can see at all. But they are definitely eating something b/c they're more green than yellow, and they are reproducing. In addition to the ulva slowly disappearing, I'm noticing the rocks look cleaner, almost like an urchin would do.

And yes, I would not recommend anyone purchase them -- these came as hitchhikers in my tank, and something about it is allowing them to thrive.

 

[Spare time]

That's why I'm so surprised. I saw just one a few weeks ago and thought, "cool, well that won't last..." And now there are many.

I have lots of coralline on the rocks, and LOTS of ulva (which, honestly, is now disappearing but that could also be due to my pitho crab), and not any GHA or bryopsis that I can see at all. But they are definitely eating something b/c they're more green than yellow, and they are reproducing. In addition to the ulva slowly disappearing, I'm noticing the rocks look cleaner, almost like an urchin would do.

And yes, I would not recommend anyone purchase them -- these came as hitchhikers in my tank, and something about it is allowing them to thrive.

It's awesome they are thriving. I'm jealous

 

[SlugSnorter]

That's why I'm so surprised. I saw just one a few weeks ago and thought, "cool, well that won't last..." And now there are many.

I have lots of coralline on the rocks, and LOTS of ulva (which, honestly, is now disappearing but that could also be due to my pitho crab), and not any GHA or bryopsis that I can see at all. But they are definitely eating something b/c they're more green than yellow, and they are reproducing. In addition to the ulva slowly disappearing, I'm noticing the rocks look cleaner, almost like an urchin would do.

And yes, I would not recommend anyone purchase them -- these came as hitchhikers in my tank, and something about it is allowing them to thrive.

their are a few elysia species tossed around in the hobby, they are quite understudied. I know they some believed to eat Penicillus and Halimida algae in the wild, although again, quite understied (as with most nudis)

 

[Lyss]

their are a few elysia species tossed around in the hobby, they are quite understudied. I know they some believed to eat Penicillus and Halimida algae in the wild, although again, quite understied (as with most nudis)

Their presence has definitely diminished since August but I still see multiples every night. Truly fascinating.