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2 unrelated mercs, any suggestions?


Staff member
Jul 13, 2008
Well, my wonderful LFS had another merc in today. As Mongo has been so stubbornly planted in the same den for more than a week, I decided to bring this one home.

Right now it is in a critter keeper where it will be for at least 24 hrs as there is a snow storm right now so were planted at home for a while. The way I see it, I can get a tank divider to cut the tank in half- I have one but it's too short. I can get a larger critter keeper and drill holes in it for a more permanent box in the tank with little trouble. Or I can keep him in the current keeper for a few more days then let him loose with Mongo and see how it goes.

All this is assuming it survives acclimation. As mentioned, it's in the critter keeper now, I bought it a piece of rock with suitable sized holes for dens and put some small shells in so it can choose and apartment and door. I put in a hermit crab but this one doesn't seem as excited by them as Mongo is. I've placed lots of LR around the keeper on the outside of the box too add more privacy, but it's watching me as I type.

So, what suggestions do you fellow TONMOers have for me?


Staff member
Sep 4, 2006
You are on your own here. We have had very good luck this last year with multiple mercs in a single tank but all have been either found or born together. The mercs only seem to be agressive towards food but we really don't have a lot of observations. At one point Sisturus would chase Dusa agressively but Dusa would go into the LR and Sisty did not follow. Eventually this activity stopped altogether and I think it had to do with sexual maturity more than establishing a domain.

If either is female they have likely already mated once but the possiblity of a second mating exists with mixed fathers or removal of current sperm. If both are female, you may have a good beginning on some diversity but don't get anything for the big tank :razz: or you might HAVE to do the master bedroom in octo tank. Aquarium born, long term survivors have been 5-6 of the hatching, regardless of the size of the hatching but Greg had more to survive this time (I think, he has not posted numbers recently - hint hint).

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