Randall's Assessor behavior question

mkoop

New member
Hello all,

I purchased a Randall's Assessor (ORA bred) about 6 months ago. He was in a 40g QT for about 4 months with 3 small female bartlett anthias. I gave him extra time in QT because when I received him from LA he was likely the smallest fish I have ever kept. I wanted to give him plenty of time to fatten up before going in the display. In QT he often 'socialized' with the female anthias.

After the 4 months I thought he would be large enough to do okay in the 180 display. I moved him in. He is absolutely beautiful but I so rarely see him. I apologize if this is a daft question but are assessors nocturnal? Or is it possible he is just extremely shy? I feed frozen pe mysis twice a day, he attends one of the feedings and I have seen him eat on numerous occasions (he has been in display for about 2 months at this point). Tank goes lights on from roughly noon - 10pm (AI Sol with controller on ramp schedule).

My little blue buddy only ever shows up at my pre work feeding at roughly 7am. Upon the initial starting of the royals ramping he disappears to his hiding spot. When lights are out he swims open water without fear, for a few hours a day even, on days off I have seen him from about 6am until lights ramp at noon, I haven't seen any of the other inhabitants chase him or show any aggression what so ever. He has swam right next to most of them with complete disregard... until the lights come on.

Could this possibly be a product of keeping him in QT with no lights for 4 months? The 3 female anthia's I added do not behave in this way at all.

Other inhabitants:
1 Lineatus Wrasse
1 Male Spotted Mandarin
1 Female Spotted Mandarin
4 Female Bartlett Anthias (1 large 3 small and young)
1 Male Bartlett Anthia (large)
2 Ocellaris Clowns
1 Diamond Goby
1 Kauderns Cardinal
1 Tailspot Blenny

and of course the assessor
 
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Assessors are a basslet, which as a group are more shy than your average fish, with some being more bold than others. As far as basslets go, I find assessors to be somewhere between a gramma and a liopropoma. It can take them awhile but generally they become fairly outgoing, staying in the open, perhaps not as much as your wrasses and anthias, but out nonetheless.

As far as aggression from others, your fish list didnt seem problematic.
 
They are shy fish. I have yellow assesors in my tank at home and it took 6 months before all 4 of them were out with the lights on.

At work I have one Randalls, who is out and about all the time and is comfortable with the lights on. But I would consider him the exception. I have kept assesors for decades, and they are normally shy fish.

Give him time and he will slowly adjust to the community tank.

Dave B
 
We have three randalli and 8 gold assessors in our 205. On any given day we see 8-10 of them. We almost never see all 11 at the same time.
Be patient. It took our first gold assessor years to be out regularly (we bought her in 2009), but now we see her every day, almost all day.
 
Thanks everyone, glad to hear this seems expected. I wasn't even aware I could have more than one of these guys in my 180, I've been very careful to try and not cause any stocking issues. I may have to look into getting this guy a buddy or two.
 
I had a Yellow Assessor in a 28 nano cube for almost year before it would come out even to feed! It would just stay in the back of the tank and eat food on the surface or pieces that made it to it. Then one day it started staying out in the open, nothing changed in the tank. Now its in my 50 cube and is out almost all of the time.
 
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