Green Porcelain Crabs at surface of water and climbing out!

[SauceyReef]

I got a 6 green porcelain crabs from ReefCleaners. 2 went into the Evo, 1 went into the six gallon orb, and the other 3 went into the six gallon Mangrove tank. The 3 in the Mangrove tank have been climbing up near the surface of the water since adding them a few days ago. 2 of them are on the mangrove stalk literally as far up as possible hugging the surface. This morning I found the 3rd literally out of the water on the side of the glass. If I poke them they react, but dont really leave the area. I do see them fanning sometimes.

Is this normal for them? A sign something is really wrong with the tank/water? I have corals, hermit crabs, the mangrove, other life in there no problem. The other three in my other tanks dont seem to be doing this. In fact I have never heard of them doing this.

 

[SauceyReef]

Came home and they’re all still in the same place.

 

[yanetterer]

My first thought is low oxygen levels, but it looks like you have good aeration.

When I tried multiple porcelains (the white ones) in a 30 gallon breeder they quickly killed each other until one was left. I haven’t read anything about them being aggressively territorial, but have you seen any aggression towards each other?

Have you tested any water parameters?

 

[SauceyReef]

My first thought is low oxygen levels, but it looks like you have good aeration.

When I tried multiple porcelains (the white ones) in a 30 gallon breeder they quickly killed each other until one was left. I haven’t read anything about them being aggressively territorial, but have you seen any aggression towards each other?

Have you tested any water parameters?

Salinity: 1.026
Temp: 76

Agreed - it cant be the aeration as I have the bubbler air tube, and a Hygger Mini in there. Plus shouldnt the Mangrove be reelasing oxygen as well? (not sure if roots do that). I just added these 3 porcelains a week ago and they went through horrible shipping delay of 6 days. I had bought six of them. 3 went into the Mangrove Vase, 2 in the Evo, and 1 in the Reef Vase. None of the other ones are doing this and are hiding in the rocks. I contacted reefcleaners - they said they could just be looking for the most flow. The spot would make sense, but still the behaviour is super odd. The two on the mangrove stalk are right by each other. And again I found one out of the water yesterday on the side of the glass..

The tank struggles to keep any corals alive. I always assumed this is the Mangrove just sucking the life/nutrients out of the tank. The vase next to it is beautiful, and runs the exact same.

My tests on the tank are limited because I dont have any important corals in there, and it is more so to keep the Mangrove alive and happy which is never a problem.

Salinity: 1.026
Temp: 75
Nitrate: 0
Phosphate: 0
Age: 2.5-3 years

 

[SauceyReef]

1. 13.5g Fluval Evo
2. 6g reef bowl
3. 6g mangrove vase

 

[SauceyReef]

Like look at this…This can’t be normal!

I’m tempted and occasionally try to grab them to plop them in the other tanks, but they scurry down when I do.