I think it's a loach...

He wont hurt any other loaches. They love to live with others, like gangs of 6. Mine always "Hug" each other. They play all the time, look like otters. They are like puppies of the tank ;) He will make you a fan, Get him some buddies, they will make you laugh!
 
I love dojo loaches, they are awesome. I loooooooooove to see them sleep in the plants. hehe
 
Heh, okay... well, my loach still kind of creeps me out in appearance. One of my friends compared him to "Barry" that giant sea worm that was found in that aquarium (http://www.dailymail.co.uk/sciencet...rium-staff-mysterious-attacks-coral-reef.html), which didn't help.

But I'm already starting to like him... I think he's playing hide-n-seek with me. He'll be sticking his face up against the glass at the front of the tank and when I approach he'll dash away into the PVC pipes at the back of the tank. And then he'll stick his face out from one of the exits and come dashing back up to where I am. I don't know why he's doing it, but it's really cute! ^_^
 
Dojos are very non-aggressive. He needs somewhat cooler temperatures than your other loaches though. The maximum temp for them is around 74-75F, if they get over that consistently it shortens their lifespans. If you can, I'd say get him a 55g coldwater tank and some buddies.
 
I have five dojos at the moment. They are fun to watch and have shown no aggression. I have had them nip at my hands while planting the tank but it was not painful in the least. I feed mine spirulina, large cichlid pellets, and shrimp pellets. They also will come up and eat flake as well as many frozen and live foods. I actually have not found anything that they wont eat. They are very easy to keep. If you have room you should get atleast two more as they like to be kept in groups. They are amazing at cleaning gravel as well.
 
He won't bother any smaller fish whatsoever. Baby crays and shrimp is another matter, they'll be snacks if they're smaller than his mouth (AKA tiny ;)). I don't think weather loaches eat snails, but I'm not sure, maybe a loach freak like Lupin will chime in like he always seems to do in all the bottom feeder threads :D.

They can get 10" long I do believe, like groups, and should be kept at the cooler side of tropical, or full on coldwater. They're pretty cheap around here, 2$ each.
 
Perhaps I'll move him in with my Marmorkrebs then. They're a non-aggressive crayfish and he's more than welcome to eat their never-ending broods if he seems interested in doing so. And they already live in an unheated tank, which is usually between the high 50's to high 60's (good temperature range or no?).

If I get him some more friends, will they have to be the same size? I've never seen a loach this big at any of my LFS before. And on the websites (like liveaquaria, petsolutions, etc) they all seem to be shipping them at the 2-4" range. Oh and will coloration matter to him? I'm seeing more of the "golden dojos" for sale than ones with the coloration like mine.
 
They don't need to be the same size or color. The temperature range should be ok, I think, not entirely sure. That tank should be dojo paradise as long as the adult crays leave them alone. :)
 
lol cute the puppy dog of the tank the temp in that tank should be perfect. There are two species of dojo one reaching a max of 10" and another that reaches 20". I used to keep mine with ghost shrimp they never touched i guess i got lucky. be for warned that they shed their skin when they grow it looks like their getting something but you'll see a floating opaque bag in the tank within days. He might even act different like not eat or play but he'll be back to normal soon.
 
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