Orb-shells (sphaerium corneum)

[JK]

Has anyone ever tried these in aquaria?

They seem to survive in very small still ponds of only 2-3 gallons, so was wondering if they are suitable.

[Terran]

They seem interesting....I would like to hear more about them if anyone has tried them in their aquariums.....

All Ive read is this about them...

Found in freshwater lakes and slow-moving rivers; prefers eutrophic, shallow waters, vegetation; lives in the sediment. Can live up to 3 years, mature at 4 mm (sexually mature as early as 3 months old in Europe); hermaphroditic; eggs incubated in a brood-sac in the parent; embryos develop and are released as miniature adults; suspension feeders on algae and bacteria.

[JK]

They seem pretty happy

[Terran]

How much do they move about in a given substrate?


Do they burrow and move around on the surface of the substrate?
Or do they burrow and move about below the surface of the substrate?

or both?

[JK]

I only collected them yesterday, but so far the majority have stayed pretty much where the landed. They spent the first half hour or so twisting about in all directions, but only a few wandered off.

Even in a sand substrate they don't seem to want to burry themselves.
Most are just sitting as the one in the pic.

[Terran]

Hmm well keep us updated it would be interesting if they stayed on the top like that....

Keep us updated on these guys progress....unless someone else already has experience keeping these or is actively keeping these with information to tell us....

[JK]

Six years too late, but here's an update on the Orb shells.

To my amazement these little critters have not only thrived, but have bred like crazy in my tank. They now cover the bottom with an incredible density, at least one per square inch.

[Mustafa]

Not too late in this case...as long as your reply does not take another six years. Have you been able to observe how they reproduce in your tank or do they just keep popping out of the substrate? Do you have any current pictures?

[JK]

It's impossible to see what's going on, as the tank is naturally planted and never siphoned. They live in the six year accumulation of mulm on the substrate rather than actually in it. This corresponds with the highly anoxic habitat in my ponds where I originally collected them. The really fascinating thing is they are the sole means of filtration in this aquarium, and do an amazing job too.

[Mustafa]

That is very interesting indeed. What temperature extremes (on the upper end) have they been exposed to?

[JK]

The aquarium has no heater as such, so just goes up and down with the room temperature. During the day when the light has been on a while it has reached 86F, but not for extended periods. By the next morning it will always be back below 80F ,even during the summer here.

[Mustafa]

Thanks for the info. Seems like they can tolerate quite a range...even if it's short term.