I forget, what was the origin of this thread :lol:

you're supposed to be bashing my ideas!
jokes jokes

but i think i am going to go with a single return instead of 2, less holes, less plumbing less pumps less chance of failure, and probably cheaper.

That should be all you need on that small a tank.

now more questions:
1 the tank is 6.6 gallons i want around 40x turnaround, thats 264gph. is a custom overflow gonna be able to handle that? i guess f its custom, than well i can just customize it?
but mainly what im asking is would it have to be big, too big.
2. to achieve 264gph what are my options for pumps/powerheads, since im just going with a single pump, i would like to be able to throttle it down, or even be able to use a simple controller with it. options?


3. plumbing, what size am i looking at to accommodate this flow 3/4? and should i go rigid or flexy? herbie or durso?

If you build an actual external overflow on the back of the edge and notch the acrylic on the back basically all the way down it should be able to handle the flow but to get the edge effect the water level has to be above the glass top which limits you to a very small surface area so you don't have much tolerance so using a fine mesh screen is probably not a good idea making it difficult to keep smaller fish or shrimp. For that flow rate a 1/2" return and a 3/4" drain will be sufficient.

Like I mentioned before though I think you're heading down the hardcore overkill road but it's up to you. My LPS and soft corals do great with only 50-60gph. SPS have their place but I've never seen a pico tank with SPS look as good as one with LPS and soft corals. Often we get the idea that the uncommon is cool and impressive however sometimes the more common approach results in a more impressive tank.

Also I suggest you do a simple test to determine if the tank can handle the flow appropriately. Fill the tank will water and place the desired substrate in it. Use a maxi-jet 1200 or equivalent power head placed in the tank and see if you can direct the flow in such a manner so the substrate doesn't get too disturbed and remains level and evenly distributed.

yes i will definitely check and make sure that the substrate stays put, i dont think it would take too much to turn that little tank into a giant cloud of dust, ive read up a tiny bit on substrates, no one seems too crazy about the crushed coral substrate, mostly cause of the lack of surface area compared to fine sand, and there were some complaints about debris being trapped in there, should i rule the option out? is it really much worse than sugar sized aragonite etc?

and im not a crazy flow monster, im just an amateur reefer who doesnt understand limits :mrgreen:

I use crushed coral in the edge and prefer it to fine sand but it's personal preferance but it is obviously better for higher flow tanks.

how do you do with nutrient export on yours? do you run a large skimmer, massive water changes, or run a nice fuge? or a combination of these things.

No skimmer or fuge. I use a wet-dry system in a modified canister filter and do monthly water changes of around 25%. I only have one goby and a ribbon eel with the corals so I don't feed that often, around 2-3 times a week. Tank is too small IMO for stuff like skimmers and refugiums.