Unhappy gigas

ReeferHD · Dec 16, 2022

Got a gigas clam 2 weeks ago and it looks bothered by something. Already inspected for pyramid snails and anything else growing on its shell, it’s about 7” I feed reef nutrition phyto every 3 days, I have a crocea that’s doing great and growing, haven’t seen any fish pick at it either.
Ph: 7.9
Nitrate: 24
Phosphate: 0.1
Calcium: 407
Mag: 1415
Alk: 7.9
Salinity: 1.026

I was thinking it could be PMD but not sure.

MarineandReef Jaron · Dec 16, 2022

So sorry to hear about your Gigas. I have been dying to get one for about a year. It may be pinched mantel. We have some experts here that can help. From personal experience, it doesn't look extremely bad at this point so I think he still has a good shot.

MarineandReef Jaron · Dec 16, 2022

@OrionN

Mr. Mojo Rising · Dec 16, 2022

There is no white at all along the top of the shell, thats not good, means its not growing. Just make sure its getting as much PAR as possible.

OrionN · Dec 16, 2022

What is the time frame of these pictures.
Top L the clam looks fine. That is how Gigas normally look, possible not as well extended as it should be. Top R show mantle irritated and bothered by something. If this change stays the same place day after day and worsen as the day go on, and there are no irritants (aiptasia on the shell right there for example) then it is possible/likely PMD
lower L show a clam that is not healthy, the shell not growing. The retracted mantle may or may not mean much unless it stays like that, not getting better. Sometime light flashes and/or shadows cause the clam to be retracted temporally.

Healthy Gigas at this size should growth like gang buster, like 1/8 of an ich or more per week. I sometime can see growth between morning to evening (or one day to the next.)

Hopefully whatever bothers him was from the previous owner and it recover and do well for you.

ReeferHD · Dec 16, 2022

OrionN said:
What is the time frame of these pictures.
Top L the clam looks fine. That is how Gigas normally look, possible not as well extended as it should be. Top R show mantle irritated and bothered by something. If this change stays the same place day after day and worsen as the day go on, and there are no irritants (aiptasia on the shell right there for example) then it is possible/likely PMD
lower L show a clam that is not healthy, the shell not growing. The retracted mantle may or may not mean much unless it stays like that, not getting better. Sometime light flashes and/or shadows cause the clam to be retracted temporally.

Healthy Gigas at this size should growth like gang buster, like 1/8 of an ich or more per week. I sometime can see growth between morning to evening (or one day to the next.)

Hopefully whatever bothers him was from the previous owner and it recover and do well for you.

Thank you, how long should I wait before deciding it is PMD? And if it is, should I do anything before doing FWD?

ReeferHD · Dec 16, 2022

So I removed some of the sand from under the clam. Looks a lot better now, not perfect but I think it just needs time, will keep updated

OrionN · Dec 16, 2022

He looks OK. As long as the irritation is getting better then just watch. If it does not or getting worst then treat him.
best of luck with him. Hope he was from poor condition and is better now in your tank.

outerbank · Dec 17, 2022

Gigas are pretty tough clams. Keep conditions good and make sure nothing is bothering the clam and it should recover.

ReeferHD · Dec 17, 2022

Doesn’t seem to be getting better, I think I’m going to dip it

Scorpius · Dec 17, 2022

FW dipping it will most likely kill it if it's already weak. Been there, done that. Have you tried running carbon for a few days?

ReeferHD · Dec 17, 2022

Scorpius said:
FW dipping it will most likely kill it if it's already weak. Been there, done that. Have you tried running carbon for a few days?

I run carbon all the time because I have many leather corals

ReeferHD · Dec 17, 2022

I am just worried if I wait too long the clam will be too weak to handle FWD

Maximus · Dec 18, 2022

I think I have the same problem with my gigas. I got the gigas about 5-6 days ago.

minus9 · Dec 19, 2022

These clams need light, if you’re not seeing new shell growth, then it needs more light. Usually clams can take a day or two in new tanks/settings, but should look normal in no time. I always treat clams as if they came from shallow water and give them as much light as I can. I find most issues start from not providing new clams with enough light. These are very adaptive animals, so acclimation to light doesn’t need to last that long.

MinnieMouse2 · Jan 2, 2023

Are these the 500.00 dollar Gigas. Yikes. I would move it around to see if it's maybe not liking that area. Maybe less light if you are blasting it while it recovers. They move to an area they like when strong. I also feed SD Aqurists clam food from Reef Nutrition. Local store orders in mine. SDAquarist™ is a blend of the 6 most widely used marine microalgae for a wide variety of invertebrates. For me, FW dip is the last resort. It use to be the first, but I have never saved one with a FW dip. https://reefnutrition.com/products/sdaquarist

Sir Bubb · Jan 6, 2023

How are they doing?

Maximus · Jan 7, 2023

Mine is doing fine. I looked online and saw a few others that looked like mine. I hope it extends its mantle more in the near future but it definitely seems healthy. I decided not to give it a fw bath. Btw, the gigas sits at the bottom of my 16" tall tank bathing in light produced by a 400w 20k Radium MH with 4x T-5 blue plus bulbs. It's receiving 300+ par in the tank.