First Sump Design - need advice

[jonny19ireland]

Hi All,

I have a small mixed reef tank (170ltr) now about 4 years, and my two canister filters are finally starting to die, so rather than replace them I'm getting a small sump built. I used one canister filter with bioballs and high flow which fed my UV before heading back to the tank. The second canister was low flow and filled with Live Rock and then fed a phosphate reactor before heading back to the tank. I also run a skimmer and Ozone unit.

I've never had a sump before and the space I have available is VERY small so quite unsure of my design and looking for help/guidance. Dimensions will be 40cm x 30cm x 40cm (LxWxH).

I'll be putting my skimmer and two Reactors in the sump (Deep Sand Bed and Phosphate Remover), and these will take up the majority of the space available.

I've attached the initial design I have for the sump. I'm torn between the two plans I have attached (elevation is more or less the same for both designs), as I'm unsure if the spare space (possibly for extra Live Rock or a TINY fuge) would add much value as a separate compartment given it's tiny volume.

Hoping someone with a lot more knowledge than me can give more some advice/feedback on the designs.

Cheers

 

[lion king]

I love the simplicity of a straight 3 chamber sump, like your plan A.

 

[jonny19ireland]

I love the simplicity of a straight 3 chamber sump, like your plan A.

So ditch the TINY chamber?

I guess with the 3 chamber setup I can still put some frags and extra LR in the last chamber if needed.

Not to great with water levels etc, that I've seen in other sump designs...can you tell me if the chamber heights seem ok/consistent enough?

Lastly - not sure if I should pump the water from the tank to the sump or have a direct syphon. Can you advise?

 

[lion king]

I'm not an expert, but here's my 3 chamber sump that I based on the design of a trigger systems sump. I have my skimmer in chamber 1 with the filter socks, baffle is slotted to flow through. Chamber 2 is a refugium; I put a media rack between the 2 baffles going into chamber 3, which is the return section.
From the tank to the sump you would want to use some type of overflow, I take it that the display tank is not drilled so you would use an overflow box that hangs on to the tank.
Your water level in your sump may be a bit high for that volume, you will need enough space when your return pump is off that the volume of water that overflows from your tank will not flood your sump. In similar size sumps I've seen water levels more like 15-16cm. The only baffle that matters for your water level,is the baffle before your return. The baffle between chamber 1 and 2 functions better as a flow through baffle rather than a overflow type baffle. So the water level in your sump would be the same all the way to return pump. You have to take into consideration what water level your skimmer needs to be effective in as well, so when purchasing a skimmer this must be considered.
When you start putting it together you'll probably find there's not that much room in the size sump you are working with, keeping it simple will be best.
These are nice overflow boxes, some you drill some hang on. http://www.eshopps.com/products/overflowboxes/
Just to give you some reference, some of the smaller skimmers could use as much as 16cm of space in the sump, and need as much as 17cm of water level.