I like you sooo much right now
LOL
The 4 bulb T5 will be hard pressed to keep up the the most light demanding corals. It can be made to work depending on the height of the lights from the tank and the placement of corals below the water line. I would recommend looking into upgrading to a 6 bulb fixture, MH lighting or LED lighting if your budget allows for it in the future. If not looking into some of the less light demanding SPS that you may come across such as Monti caps or Hydropora.(sp) The individual reflectors will help but you are still running only 216W of lighting vs most 24-25" deep tanks with run a 250W MH or comparable with decent reflectors.
Lucky for you the father Bangaii will host the fry in his mouth until they become a bit larger. Your first concern will be capturing the young fish without causing bodily harm and before they become a snack for your larger fish. This naturally occurs by using a long spine urchin for protection. One thing that can be done is a chem light fry trap. I'll attach a link below for construction. Also once the fry are released from the father a simple 10 gallon tank will suffice for raising them for awhile. Here is a great article from teh breeding registry that will help you out
Light trap in case you can't catch the male.
Chemlight larvae trap
Bangaii Cardinal Breeding Registry
Raising Bangaii Fry
A herbie overflow is a very simple a silent way to do an overflow using only 2 pipes. I have used one in a previous tank of mine and it is very easy to regulate. A later improvement to the design was the Bean animal silent a failsafe overflow. I will include link to both designs for you.
Herbie overflow (Note you must use a gate valve not a ball valve)
very long discussion on Herbie overflow
Basic Herbie graphic
Improved Bean animal overflow (requiring 3 holes)
Bean animal overflow
The Maxi-jet 1200 is a 295 GPH pump in "powerhead" IE pump mode at 0' head. I would look into a mini-jet 404 or 606 adjustable flow pump. Several of our sponsors carry them. This will allow you to adjust the flow down or up as your need grow.
I would need to know the dimension of your tank as well as your current aquascape to give you an accurate answer. A generic answer would be is has to do with the collision point of the water flow from the powerheads creating random current throughout the tank.
Just as a reference 1" PVC under a Pressure of 20 PSI can flow 2200GPH. Under Low pressure IE gravity it can feed 960 GPH. If you upgrade to a MAG 18you can upgrade to 1.5 if you feel it is necessary, but depending on your head height it may not be. Also keep in mind you would have to replace it all and not leave any of the old tubing behind as that would create a choke point. Your Maximum flow will be dictated by the smallest choke point. (IE You will flow less but with higher pressure at the discharge)
(Reference
PVC flow rates based on ID)
