I ve bought 2 L46 but one is dead this week.. The other is thin.. He don't eat so much. We have try to give him differents food.. but its hard.. He eat a little artemia and Brine Shrimp..
Actually he is on a hospital tank with two ground pots, an air pump and a filter.
Is there anyway to return the other one.
When buying baby zebra fry, make sure you know when they are born. Fry younger than 3 months are a very risky investment because many can unexplicably die for no reason. They require special care. It's not supprising for an entire batch to go on a hunger strike and all die for no reason. So it's better to buy your zebra fry at 6 months old as that is a much more safer investment.
The bottom picture, that one desparately needs help. Looks like it's been starving for a week or more.
Try feeding with baby brime shrimps, liquid fry from Wardleys, and crushed sinking brime shrimps pellets from Wardleys. These are very cheap food that you can get at any Wallmart (Wardleys food).
You can go back to more nutritious live food once they get bigger.
It will take weeks to rebuild their health back.
Good luck
Aw bless, he's so skinny! I certainly would not add any others to the tank he is in, if they are stronger then he will not have the strength to get to the food! Please try and get this one fed up before adding others to the tank! Although you say he is the hospital tank, surely you'll be using a quarantine tank to add any others anyway?
My guess is internal parasites. I would try Metrodinazole treated food if it is still eating. If not I would try either levamisole or flubendazole which will work dosed in the water. These are the names of these meds in the USA where all are available. I don't know what is available there.
What makes the common person uncommon is common sense.
Ammonia or nitrites present in the tank would be my first guess. They will definitely affect their appetite drastically. I've had very few bottom feeders ever whither away and die of starvation in a short period of time. If you've seen him eating, it's almost certainly not that, but some other factor keeping him from wanting to eat. You don't mention your water change regime, or the ammonia and nitrite readings. I'd be interested to hear of those, also.
I don't have nitrites but a little ammonia.. It's strange because i use cycled water.. same for filter.. The tank don't smell ammonia.. But test kit detect ammonia... So i've test cycled water, and i dont have ammonia..
I dont know why i have ammonia on a naked tank..
Ammonia is keeping the fish from eating. Do 30% water changes, remove uneaten food, supplement the tank with filter media from a cycled tank and do a prayer for your last zebra, seriously. You could add a product like Amquel to detoxify the ammonia, or Biospira to jumpstart the biological bacteria in the filtration. Not eating is the least of his worries right now. I would not add any medication at all, if he was mine. There is way more potential to stress the fish worse in his weakened condition.
As well as the water changes (as suggested above), do you think giving him a little place to hide might help? It might also be stressful being exposed like that. He might feel a little more secure if he had something to tuck up under. A little piece of wood, or slate or something?
I certainly would not add any others to the tank he is in, if they are stronger then he will not have the strength to get to the food! Please try and get this one fed up before adding others to the tank! Although you say he is the hospital tank, surely you'll be using a quarantine tank to add any others anyway?
I look on him and i've seen a bacterial attack too 
