I am new to 3reef, but wanted to document my 120 gallon upgrade. I currently have an RSM 130D (see here). This is a 34 gallon all-in-one, but I added an overflow with DIY sump, ATO, DA Controller, and a refugium. After having this setup for a year, I learned a lot but I would like a bigger tank. There are a few reasons for this: Quiet. Very Quiet. I know this is hard with a reef tank, but my design is going to great lengths to make it as quiet as practical. Higher watt lighting: I currently have 110W of power compact lighting, but I would like to keep some animals with greater PAR needs. More volume: more/bigger fish and enough live rock to keep a healthy mandarin. Get everything inside the stand. I currently have the chiller and top off water outside the tank and I don't like the clutter. The primary reason, however, is that I like designing and implementing tanks I probably enjoy building them as much as I enjoy admiring them. I don't quite have a stocking plan, but I figure with 120 gallons and a decent amount of PAR, I should have lots of options. I had a tank plan for my last tank and the reality is that LFS availability drove my plan more than my initial stocking list. Based on available space in my living room, here is my current thinking (I explain some of the reasoning in more detail below): 48"x24"x24 Trimless/Rimless style tank Coast-to-Coast External Overflow (5% drain drops straight into sump) Toothless design (I will use egg-crate above the water line as described below) DIY or off-the-shelf LED lighting Refugium with DSB Quiet Skimmer Digital Aquatics Controller w/ATO Vortech MP60 Other reactor and dosing paraphernalia Quiet Since quiet is my main goal, I spent some time researching this on line. In reef tanks, a large source of noise is when water flow becomes turbulent and mixes with air, so one key to a quiet tank is laminar flow and designs that don't give the water too much opportunity to mix with air. Several people swear by the BeanAnimal overflow design. This is basically a Herbie overflow with a third emergency only drain. The main advantage of the Herbie design is that 95% of the draining happens through a submerged standpipe so no air can mix to make gurgling noises. The other 5% or so drains along the sides of the PVC as laminar flow, so no noise. This also assumes you submerge the standpipes in the sump, so there is no splashing or bubbling noises when the water enters the sump. Here is a conceptual idea of what the tank will look like: I approached a few builders and they all said they would not put an external overflow on a rimless, so the eurobracing is going to be required. I also looked at an internal overflow, but I like the cleaner look of an external overflow. Overflow The driver behind the toothless overflow is avoiding the trickle you can get from the turbulent flow created by teeth. A long thin sheet of water is taken instead. This opens up the problem that snails and fish etc can get into the overflow. I solved this in my current DIY sump by using egg-crate 1/4" above the water surface, but nothing comes into contact with the water. It's a little hard to see, but the egg-create on the left shows this: Lighting I live in CA so electricity is expensive. I pay around $0.25 per KWh. ANd if I go over certain limits, the marginal cost of non-essential usage can get into the $0.40s/KWh. Ouch. So, nothing offers the PAR/Watt of LEDs, so that's my plan. I have designed a 46"x10" hanging fixture that uses 105 High-power LEDs. I may end up buying off-the-shelf, but I think this would cost about $1300 to build for 250W of LED lighting. Here's the idea: Heat Sink is 46"x10"x1" (LxWxH) 105 LEDs 71 CREE XR-E Bin D316 Royal Blue (shown as blue) 22 CREE XR-E R2 Cool White (shown as white) 12 CREE XP-G R5 Cool White (shown as yellow) 2.09:1 Blue:White Ratio ~250 Watts That's all for now. More later.