Stocking Again!

[Leesey]

Hi 
I have kept marines for a period of time and when we moved house we shut the thank down and were looking to re set it up with new skimmer etc.
However times have changed and with another baby on the way we are going to use the tank for tropical fish instead.
 
Its measures 36 inches wide, 27 inches deep and 27 inches high.
The sump measures 30 inches wide and 18 inches deep and the water level come about 10 inches high so the working system volume is around 518 litres.
 
i am wondering what type of fish you would recommend for this. 
My daughter is obsessed with sharks (she is 3) but potentially some form of Pictus Catfish may suffice (if appropriate)
 
Any thoughts please say.
 
I will be having plants in this and a sand base (i think) 
 
The flow through the tank will be provided by a 6000 kph return pump in the sump and supplement by a Jebao powerhead to produce a wave (natural feeling) in the tank and to provide more circulation.
 
I may in the future be looking to have a c02 set up but i am totally unsure on this.
 
the lighting will be provided by a white led which i currently have.
 
All thoughts on stocking and plants etc please say as i am relearning in this side of things. 
 
Thanks in advance 
 
Jon

 

[Ninjouzata]

The dimensions will limit you a bit for bigger fish. Pictus cats need 48x18x18 so those are out

 
A lot of small fish though will make a stunning display!
 
What is your pH? Is your water hard or soft? What size fish & color are you looking for? Any favorites?

 

[Leesey]

We would like plenty of movement, The water is not that hard and the ph is between 6 and 7.
 
Not particular colour just plenty of movement and a good variety.
 
Jon