What is this?

Mary Carmen · Feb 26, 2023

Hi!
I added a bottle of copepods two days ago and I always like to take my magnifying glass (20X-12mm) to look at them. This time, I found these… can someone tell me if these are female copepods with eggs? They look really big to be that, if you have any idea of what this is, let me know!!
The tank is a 5 year old 29 g biocube.

I never finish anythi · Feb 26, 2023

Interesting, looks like a flat worm . I'm new to the hobby tho so it's just a guess.

Mary Carmen · Feb 26, 2023

I never finish anythi said:
Interesting, looks like a flat worm . I'm new to the hobby tho so it's just a guess.

The inside looks like it has eggs with a darker center.

TokenReefer · Feb 26, 2023

Do you have any snails? I had a similar pic and post a while back and we figured it was nassarius eggs

Mary Carmen · Feb 26, 2023

TokenReefer said:
Do you have any snails? I had a similar pic and post a while back and we figured it was nassarius eggs

I have 9 of them. I love them. I hope you are right. Will they actually reproduce in my tank?

TokenReefer · Feb 26, 2023

Mary Carmen said:
I have 9 of them. I love them. I hope you are right. Will they actually reproduce in my tank?

I no expert so I dug up that thread
Thread 'Egg sacs..' https://www.reef2reef.com/threads/egg-sacs.949240/
Unfortunately I don't think they'll survive through thier life stages..

EeyoreIsMySpiritAnimal · Feb 26, 2023

Mary Carmen said:
I have 9 of them. I love them. I hope you are right. Will they actually reproduce in my tank?

Reproduce, yes. Actually have offspring that survive? No.

Mary Carmen · Feb 26, 2023

EeyoreIsMySpiritAnimal said:
Reproduce, yes. Actually have offspring that survive? No.

Why is that? Do they need special conditions?

Mary Carmen · Feb 26, 2023

TokenReefer said:
I no expert so I dug up that thread
Thread 'Egg sacs..' https://www.reef2reef.com/threads/egg-sacs.949240/
Unfortunately I don't think they'll survive through thier life stages..

I am going to read it now… but one more question- did the eggs hatched?

Mary Carmen · Feb 26, 2023

Also! I just remember seeing some of my nassarius snails taking a walk on the front glass!

TokenReefer · Feb 26, 2023

Mary Carmen said:
I am going to read it now… but one more question- did the eggs hatched?

Yeah appeared to hatch days later but I have the same amount of snails unfortunately

EeyoreIsMySpiritAnimal · Feb 28, 2023

Mary Carmen said:
Also! I just remember seeing some of my nassarius snails taking a walk on the front glass!

I guess it depends on what you actually have in your tank. Nassarius vibex - The small ones generally desired in the hobby only eat dead stuff or extra food ... carrion essentially. Successfully breeding these in captivity has eluded even the most experienced aqua farmers so the chances they will reproduce and join the rest of your clean up crew is extremely unlikely.

There are other snails that look a lot like n. vibex that eat algae, and some of these can reproduce successfully but aren't going to actually be nassarius.

Regardless of the theoretical survivability, most eggs, hatchlings, etc very quickly become a meal for the other tank inhabitants.

(If your "nassarius-looking" snails are regularly on the glass or if they climb on the rockscape at all, they are not the kind you want in your tank.)