At what length/age do Derasa Clams spawn?

[AstroCoral]

Hello all,

I am wondering at what point Derasa clams become mature enough to spawn? Is it based on a certain length or age? It seems there is limited information online about when a Derasa clam can begin to spawn.

 

[Xanthurum]

probably not the exact answer you are looking for but I have seen a derasa that was around 10 inches spawn. Not sure how old it was at the time but it spawned after a water change.

 

[AstroCoral]

probably not the exact answer you are looking for but I have seen a derasa that was around 10 inches spawn. Not sure how old it was at the time but it spawned after a water change.

I think that’s a good start to the search for an answer, so a 10in Derasa (at the least) will spawn.

Maybe I’ll rephrase the question for others users: What is the smallest derasa clam you have seen spawn?

 

[Xanthurum]

I think the water temps were different so the clam decided it was time lol. I will say that it spawned a LOT! In fact another water change was done a few hours later. This happened at a LFS but it was several years back. Last time I was there the clam was much larger, probably around 14 inches but that was over a year ago. I’ll tag @Epic Aquaculture because his derasa has spawned a couple of times I think.

 

[AstroCoral]

I think the water temps were different so the clam decided it was time lol. I will say that it spawned a LOT! In fact another water change was done a few hours later. This happened at a LFS but it was several years back. Last time I was there the clam was much larger, probably around 14 inches but that was over a year ago. I’ll tag @Epic Aquaculture because his derasa has spawned a couple of times I think.

I’ve definitely read that elsewhere as well, it seems an increase in temperature will cause spawning in clams.

The issue I’m trying to navigate is that I’m debating on adding a 2in. Derasa clam to my 3 gallon tank. I definitely understand this sounds crazy but I’ve seen that it was successfully done 10 years ago in the exact same tank I own by a user on a different form (tank was operated with the clam for approximately two years before it was rehomed). I have a rehoming plan for it as it grows larger (I will be setting up a 200+ gallon tank where it will eventually end up). My concern with the 3 gallon tank is a spawning event which would likely crash a tank that small. I’m not sure that I want to take the chance, I may just wait until the much larger tank is setup and stable.

 

[Xanthurum]

IMO you would be better off with either a Crocea or a Maxima. In fact there is a chance you could keep a Crocea in that size tank long term. Just good for thought not being judgmental especially considering that both of those options tend to have more of a visual appeal over a Derasa. My heart still hurts after losing my Crocea that I grew from a 1 inch clamlet to a full grown adult lol.

 

[AstroCoral]

IMO you would be better off with either a Crocea or a Maxima. In fact there is a chance you could keep a Crocea in that size tank long term. Just good for thought not being judgmental especially considering that both of those options tend to have more of a visual appeal over a Derasa. My heart still hurts after losing my Crocea that I grew from a 1 inch clamlet to a full grown adult lol.

The Crocea clams are definitely my favorite clam but I’m not sure my current lighting intensity is going to support it. The Derasa clams can handle slightly lower lighting so I was favoring that aspect of it, I assume if the Crocea was fed regularly it may be okay with under 200 PAR of lighting. I need to do more research on this though - I would just bump my lighting intensity up further but I think I’m already starting to hit the threshold of my other corals light tolerance.

 

[minus9]

The Crocea clams are definitely my favorite clam but I’m not sure my current lighting intensity is going to support it. The Derasa clams can handle slightly lower lighting so I was favoring that aspect of it, I assume if the Crocea was fed regularly it may be okay with under 200 PAR of lighting. I need to do more research on this though - I would just bump my lighting intensity up further but I think I’m already starting to hit the threshold of my other corals light tolerance.

No amount of feeding will ever make up for lack of light. It may help an unhealthy clam, but it will only take it so far. Also, I wouldn't worry about a young clam (derasa) spawning that early. Unless there was a stress spawning, which I doubt would happen. I have a 3"+ derasa in my 10g for now, but will be moving it over to my 90g soon. As long as you have the room in the tank and you can keep parameters stable, you'll be fine. As long as your clam has new growth, it'll be fine.

 

[OrionN]

I don't know the answer to the OP question, but I do know that smaller clams will produce sperms only and larger more mature clams will produce both sperms and eggs.
You may want to send an email to Gerald Heslinga at IPSF.com. He is the one who work out all the kinks for the Giant Clam farming. He is the the person most responsible for getting the Giant Clams off the Endanger Species list.

 

[OrionN]

I’ve definitely read that elsewhere as well, it seems an increase in temperature will cause spawning in clams.

The issue I’m trying to navigate is that I’m debating on adding a 2in. Derasa clam to my 3 gallon tank. I definitely understand this sounds crazy but I’ve seen that it was successfully done 10 years ago in the exact same tank I own by a user on a different form (tank was operated with the clam for approximately two years before it was rehomed). I have a rehoming plan for it as it grows larger (I will be setting up a 200+ gallon tank where it will eventually end up). My concern with the 3 gallon tank is a spawning event which would likely crash a tank that small. I’m not sure that I want to take the chance, I may just wait until the much larger tank is setup and stable.

I should read more befor I post the last post. 2 inches Derasa will not spawn, but handling small tank like that is so easy. If any problem in a 3 gal, just do water change.

 

[AstroCoral]

Thank you for all the replies! I’m going to continue doing more research on clams. I may wait until the 200+ gallon is setup and somewhat matured before moving forward with purchasing a clam of any kind.