<a href=showthread.php?s=&postid=14844446#post14844446 target=_blank>Originally posted</a> by Whys
Oh come'on... I'm not the only one here. 
Ok, I'll help, too.
:lol:
Umm... for pods I'd say liverock. For macro, do the Chaeto.
I agree. Chaetomorpha rarely turns sexual, it doesn't need to be attached to anything, and it's not invasive. Caulerpa does turn sexual (then die), attaches to live rock, and is horrendously invasive. (So invasive, in fact, that several species are illegal to import into California, because they've gotten loose and taken over some areas along the Pacific coast.)
I'd recommend a shallow sandbed personally. That'll provide a good environment for copepods. I keep thinking about doing it for mine, but the argument against is ditritus trapping. I just put a dusting of different sand grain sizes in mine, but admittedly, I don't see a lot of copepods. On the other hand, my system runs really clean.
I put a 2 inch sand bed in mine, but I don't have a strong opinion on how it should be done.
You'll have to decide.
The height of your baffles is usually determined by the height of your skimmer, or in sump reactors, or what ever needs a certain amount of water height.
Agreed. My hang-on-tank refugium came with baffles already installed, so I didn't have to decide how tall they should be.
Sorry to say, a lot of this is stuff you're going to have to figure out for yourself. I have one baffle in my sump, but I can't say that is right for you, besides, I do have some micro-bubbles floating around. But then again, my sump is a very high flow. But then again, my sump uses a micron sock.... you see where this is going. 
The most common recommendation I've seen is for three baffles, with the opening alternating between high and low. That configuration supposedly removes the most micro-bubbles.
This is a complex hobby with many facets an endless options. No one actually knows what is truly "ideal". That's part of the hobby. Researching, learning, drawing conclusions, and deciding on your own solutions.
It helps to create several threads with very specific questions for each one. That will get you more responses.
Part of what makes it so hard to get detailed advice is the fact that most people have a unique set-up. If you were on a board where everyone used one of the pre-packaged tanks, like the BioCube or the Red Sea MAX, then you'd get a lot of definite answers. Instead, most RC members have their own unique assemblies of totally different pieces. We can't tell you to install this, remove that, and move the other thing 3" to the right. All we can do is tell you what we've read or seen, and what worked (or failed) for us.