First discus tank

[omaralvi]

This is my first time keeping discus. I have had them for about a month now. They all seem to be doing good at the moment. I will breakdown all the specifications.

Tank
20 gallon long barebottom
Moving them into my 75 gallon as soon as they all reach 3 inches

Stock
7 discus all about 1.2" to 1.75". I can't say exactly how much they have grown since I got them but they have grown considerably.
5 assassin snails

Filtration
API 30 Superclean
some 10 gallon filter don't know the brand

Feeding
3-5 times a day
Frozen brine shrimp, frozen bloodworms, pellets flakes, occassional home made mix of beef/chicken

Water changes
About 50% daily or every other day

Now my questions
1.How do they look in terms of
i.Health
ii.Shape
iii.Color

2. Is a 20 long okay? If so, how much longer will it be okay?

3. Filtration enough with my water changes?

4. What breed are they all? From my research, I've gathered that there are two blue diamond, 3 pigeon blood, 1 red turquoise, 1 red turquoise/pigeon blood mix. Close?