So filtration needs for a frag tank are the same as your full reef tank, it needs the same flow, good lighting and decent water quality.
Obviously because of the water level the lighting can be a bit subdued because it doesn't have to reach the bottom of a 600 deep tank.
I also read that some corals need the bio load from fish....so i might add some tangs to this tank in future
My current plan is to use the water from main tank in the frag tank whenever i do water changes
A good method is Orca bio-cubes, check out @Hails and @butcherman L-shaped frag tank, just skimmer, bio-cubes and some other offerings from Orca, such as reef x-trax cubes, good lighting and good water movement.
They also never do water changes. but each to their own.
They get fantastic coloration on corals in the frag tank, i don't recall seeing liverock in the sump.
They do keep one or two fish, but i've also seen fishless sps systems with thriving corals, so i think the "corals need fish waste" is a bit of a myth, my opinion.
When you do water changes on your main system, say for example 100L. Then you drain first 100L from the frag setup. Drain 100L from main system into frag system. Then you fill the main with the freshly mixed salt water
Hi Riaan thats exactly what i was planning
Currently not doing any water changes on main tank , just dosing and odd top ups wud salt mix
Will have to start doin more regular water changes to feed into frag tank...
@ Camel also agree with sps and ultra low nutrient system...will have to check growth and mayb change later.....