I'll add a few more thoughts. Nothing too spectacular though.
Rubbermaid sumps are fine. They will bow, however. What some people do is build an external frame and this seems to work well. The only thing is after all that effort I'm not sure you really are ahead seeing as a 20g tank is usually $20-30, a 40g tank usually $30-50, and so on, and cheap tanks tend to work rather well as sumps. (Right, Jonathan?
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I plan to keep, in the long-term (after the tank is very well established), acropora and other stony corals, [...] , anemones,...
This part .... um .... this part, uh, it does not sit all that well with me. Where to begin. First of all, typically anemones and stoney corals are not all that compatible in a tank. Usually how it goes is, anemones sting, and stoney corals get stung. Soon, no more stoney corals. To start having a mixed biotope like that, you need to do very careful planning, very careful placement, and very careful species choices. One of the smaller anemones can work, but as soon as you start getting into things like carpets, sebaes, ritteris, LTA's .... if well-cared for, these animals get BIG, and require a setup which has been built with
only their needs in mind. Actually even BTA's can get big. Not unheard of to see a 16" BTA.
Second, conditions that anemones like, are not the same as conditions that stoneys like. Obviously there is some overlap. The one thing that I think stoneys can handle better than anemones, are slight pH fluctuations. Going from a pH cycle from 8.4 day/8.2 night to something like 8.3 day/8.1 night, you won't even notice this in your stoneys (I didn't, anyways) but it is a serious kick in the stomach for an anemone. Conversely, anemones can weather an accumulation of nitrates whereas stoneys can not. Anemones can live through 80ppm NO3 and look like it's nobody's business .... try putting a stoney into water with 80ppm NO3 though, and all you'll have is stone. Anemones also need a lot of food, and this can load a system.
Lastly (I'm sorry to babble on like this), you said "anemones" not "anemone". Multiple anemones ...... ohh. This one hits so close to home for me. So many people do it, and since their anemones are fine, they'll be quick to tell you that there's nothing wrong with it. The problem is .... it's like sitting on an undetonated WWII ordnance. Sure ... it hasn't blown up in the last 60 years, that's not to say it won't blow up tomorrow. Anemones can engage in a form of chemical warefare sometimes referred to "diffuse competition." Basically, things like shed nematocysts, and perhaps other chemical emissions, can wreak havoc on other animals.
If you've read this far. My apologies for going on and on and on. (Wow, there's an hour of typing I won't get back..
) My intent is not to sway you off any idea, but just to say this can be a delicate balancing act that is hard to get right. Lots of people say "I want a reef tank with blah blah blah, oh, and an anemone." It's always an afterthought. Anemones are the ones to suffer as a result, barely 1 in 5, or 1 in 10, (I do not know the exact statistic) tend to live beyond a year in captivity. Which is a travesty, because they're literally immortal in the wild, and plus it's completely possible to do well with anemones when you have the requisite planning and care. Anemones are fabulous creatures, but they're fussy and require a lot of planning. If it's not done right, then it's a recipe for disaster.
Oh more thing (how many points have I made since I said "lastly" ? Sheesh, what a moron). Don't put an anemone into a tank less than 6 months old. They're way senstive to parameter swings of any kind, and like fine wine, reef aquariums need to age a little before they completely settle down and not suffer sudden unforeseen parameter swings.
[...]
With all that said, it does sound like you are well on your way to an awesome system, and I can't wait to see the fruits of your labour down the road. Good luck, and have fun!
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