Fish Came W/house! Please Help Identify

Hello,
 
I moved into an apartment in Hong Kong with a koi 'pond' out back and a tank inside with these guys. There's a language barrier with the landlord & general Chinese to English translation so having a hard time finding someone able to tell me exactly what these guys are. The landlord left me no specific directions. I want to take good care of them and am considering getting a few more or another type that's compatible.
 
Sorry for the bad pic. There's a blue light in the tank that's in an otherwise dark corner. The fish are pretty much black and white coloring.
 
Any help is greatly appreciated!
Meghan

Short answer is the fish are discus, although which exact strain I dont know. Basically they are going to need perfect clean water and are not an ideal fish for new comers because of their requirements. Did the landlord leave any food for them? If they did then keep using that food.If not its going to be a bit of trial and error for what foods they will eat. If possible try to track down some discus specific food, if all else fails mosquito wrigglers, blood worms or black worms are all normally readily taken by almost all fish including discus.
Welcome to the forum
 
This link might be able to give you more info on keeping Discus
http/www.fishforums.net/index.php?/topic/307721-discus-fish/

Hi and welcome. First thing I'd do is change that light for a daylight bulb - or if there are plants change it for a tube specific for plant growth and then start researching Discus. As Baccus said, they can be a challenge to keep especially when new to the hobby

Thanks so much for the input and the welcome! Very happy to at least know what they are.
 
I'm going to do my research now. And definitely change that bulb... hate it anyway!
 
Yes, the landlord left bloodworm cubes in the freezer. Unfortunately for the fish they don't have a choice at this point who their minder is  

As far as compatible fish with discus goes... the best answer I can give is 'cardinal tetras' - full grown, if possible.
 
 
Discus require warmer than usual temperatures, cleaner than usual water - LARGE water changes on a very regular basis.  Very low nitrates (part of the natural nitrogen cycle of the fish... and the more fish, the faster the nitrate will rise).
 
Plants, plants and more plants will be a great aid to you.  These fish are generally from densely planted regions, and appreciate the shelter plants provide.  Do have a read up on these guys and be ever so vigilant.  I would never, ever recommend any one start the hobby with discus, but that is the hand you have been dealt.  You will need to learn on the fly and quickly.
 
 
 
Do you have a RO water system in the apartment? 
Do you have a water test kit?  pH, kH, gH, ammonia, nitrite and nitrate?   
 
These fish require SOFT, ACIDIC water.  

Could you take some more photos of the discus set up?  For all we know the tank could be on a continuous drip system or similar and not need water changes or it could have a ridiculously tiny filter which means they need daily changes.  Also, how big is the tank?