Hey Riaan, thanks for the welcomed feedback.
I have some limitations in terms of the setup, I don't want to go too big as I want to keep the total system volume to be around 2000L's. The frag tank will actually be 2m long by 1200 wide. I've opted not to make the refuige a permanent fixture "on top", but rather build a small sump for that to grow chaeto in on a reverse cycle using normal cfl globes, also will help with PH swing at night.
My theory in any case is once the scrubber has taken hold, the nutrient levels would drop and start starving the macro algae growth in any case...it all depends on the balance...i.e. how much fish load and feeding I give to the tank vs. what the scrubber, skimmer, etc...can up keep up with, in terms of exporting out of the system.
Actually, if I could I would go for a 1.5m x 1.5m sized ATS

. I've got long arms so cleaning will actually be very easy for me. What I have not shown in detail is that the bottom end of the scrubber will have a 'half pipe' 50mm wide gutter which I either plan to slap in place when I do the cleaning or attach permanently to the bottom end. Either way it will be plumbed as well to the drainage via a ball valve. The idea being to switch the flow to drain, then giving the ATS a good rinse with the same left over water from the water change.
With regards to the cooling, I'm very much hoping the scrubber will drop the temp so that the chiller hardly comes on. The whole area will be well insulated and the twin wall polly is designed to thermally allow for cooling in hot summer and retain heat in winter. I will have to judge the water loss, again evaporative cooling could be seen as a plus....still too early to tell. Ive been running ATS's for about a year now and really impressed with their benefits that i have witnessed, as for pods...to tell you the truth I see more of those on the rocks than the scrubber itself...more food for my copperband.
My choices for the ATS screen could be acrylic, glass or plastic fly-screen. The two latter one's I use in my current setup and actually give a couple of grams different in harvest. I posted a thread and some pics of this. I'm really not worried on the aesthetics of the scrubber, actually the sound of a running water fall will be cool....helps people also understand what it takes to make this hobby tick.
In the frag tank I want to also DIY a wavebox of sorts, seen some nice designs on the web, will have to raise the glass level though.
Some good advice I got from Gix...is to try and wait till coraline algae takes hold in the tank...before I start housing any coral stock in the tank. And when I do, do so in small increments. That's the part that will really test my patience
