Discus Pair... Happy & Sad

Get yourself set up with the Brine shrimp and relax, this happen all the time with Discus and Angels. Get a 20H and put the pair in there when they spawn you will have a better chance of the Discus raising the young. When you are successful you can sell off the babies and you just paid for the tank. Think of the tank as an investment or an insurance policy.
 
To answere your cycling question you asked use the water from the main tank. It has all the beneficial bacteria that your tank needs to cycle. If you have any decor that could be moved out of the main tank and put into your new tank that will help speed up the cycling process as well. For the HOB you mentioned I would take some of your filter media from the old tank and squeez that into the new HOB to kick start the cycling process.

I had a breeding pair of angels in a 20 long when I first started keeping fish and they wouldnt spawn for me but when I moved them in to a 30g they went nuts and started laying eggs everywhere but none of them ever made it. I still have the pair they are living in my 55g with my discus. The male had an unfortunate run in with another male angel and he had the crap kicked out of him so now he has 1 eye and swimms tilted. They havent mated since that day.
 
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