What's the critical mass for Damsels to start coexisting peacefully?

[Zionas]

Keeping a group of fish for 7 years is really impressive. I’d imagine it’s much harder to do with Chromis. Do you see your Allen’s living over 10?

 

[Zionas]

How big were they when you got them and how big are they now?

 

[mort]

They were tiny when I got them, probably half an inch and just over 2 inches now I'd guess.
They can definitely live ten years as my parents have my original pair that are just over that. I don't know how much longer they will live but they don't look to have aged.

I'm not a green chromis fan really. I'd love them if they did what everyone claimed, ie kept in a nice group and didn't mercelessely kill each other, but compared to the average chrysiptera they are pretty boring. The most interesting chromis just never turn up in our hobby or are just to expensive to keep how we'd want.

 

[Zionas]

I agree. I’m also a Chrysiptera fan over Chromis any day.

 

[jt8791]

Allens are a great damsel. I've had a group of 5 for about 7 years now and they do great together. The tank is bigger (5ft) and I have two pairs and a spare but it has enough room to keep out of the way when needed. They do group at night and when not breeding though.
My experience of them is that they do well in groups and I've always advised keeping them in a group of 5 plus, but I've had a few people who didn't do that we'll with this advice and the only reason we could come up with was they qt'd in a pretty bare tank. I think they need space to get away from each other when needed otherwise they can be over dominated. That is fine in the average reef but something to consider if you qt first.
I started with a group all the same size and let them sort out their roles in the hierarchy.

How big of a group should I plan on putting in? Would be the only fish so no qt, seems like extra unneeded stress. I was thinking between 5-7, but not sure if this tank is big enough for them. See a lot of info saying they do better in a 50 gallon, but also saw others saying to crowd them like mbuna cichlids.

Edit: That's funny, this was the thread I read that on. I gotta stop researching fish, can't wait for my life rock to come in today.

 

[mort]

How big of a group should I plan on putting in? Would be the only fish so no qt, seems like extra unneeded stress. I was thinking between 5-7, but not sure if this tank is big enough for them. See a lot of info saying they do better in a 50 gallon, but also saw others saying to crowd them like mbuna cichlids.

Edit: That's funny, this was the thread I read that on. I gotta stop researching fish, can't wait for my life rock to come in today.

I guess it really depends on how brave you are. You could try the mbuna way and cram them in but your likely still see some reduction to the point where your tank can cope. I think 5 is a good number but you could try 7 if you are braver. I've definitely seen 5 work in similar sized tanks.

 

[jt8791]

I just put 40# of life rock in today and it looks bare in comparison to the amount of sand, seems way out of proportion. Oh and I now have a dsb, 4” anyways. So I may want to rethink my stocking plans.

To save time and money I may grab 2 of the medium rocks and 2 arches, the individual ones at petco. If it’s all in stock, which seems hit or miss, $70 plus tax. Cheaper than another 20# and the arches will make it look less like a pile of rocks. Still life rock, I just don’t feel like waiting till the 28th for a 20# box.

Gotta love ocd, can’t have 60# sand and 40# of rocks, it just doesn’t look right.

Haven’t come up with any other stocking ideas yet. Tanks too short for lined sh, a 55 seems more fitting for them. Sure I’ll stubble onto something, gonna stop by easy aquariums new location and fill up a couple jugs of rodi on the way by.