Newbie Looking For Help On Sump Baffle Height

[Anthony]

Hi,
I'm trying to setup my first saltwater tank (~90 gal DT and a 30 gal sump)
And I'm having an issue figuring out the what height I should make the baffles in my sump,
The sump is being make out of an old 30 gal tank. The tank is 35.5" long, 12" deep and 16.5" high. My plan was to have the DT drain into the first chamber (9" wide), pass over a baffle into the 2nd chamber (refug) 14.5" wide. then an over under over baffle setup (2" gap between baffles) and into the final chamber (7" wide) for the return.
If I make the baffles 12.5 high, I believe it should leave enough room for my DT to drain ~2" and not flood my basement and make my refug ~10% of my DT.
I can lift my skimmer up so I'm not worried about the height of the first chamber.
My question is should all the baffles be 12.5" or should I step them down, (12.5 then 12. Then 11.5. etc?
Can someone point me in the right direction,

Thanks for the advice.

 

[EricTMah]

How many gph through the system(main pump gph)?
How low will your dt drain out after a power cut?
Is your dt 48x18x24h?

Sony Xperia Z3

 

[Anthony]

Hi Eric, I measured the interior at 47.5 x 17.5 x 23.75, hoping it will only drop about 2 (still working on the overflow plumbing, it's a non drilled tank)
The pump I picked up is rated at 587 gph at a head height of 5ft

 

[heath]

Hi Eric, I measured the interior at 47.5 x 17.5 x 23.75, hoping it will only drop about 2 (still working on the overflow plumbing, it's a non drilled tank)
The pump I picked up is rated at 587 gph at a head height of 5ft

Anthony, you are asking some really good questions, good luck with the build and lol...

 

[EricTMah]

Hi Eric, I measured the interior at 47.5 x 17.5 x 23.75, hoping it will only drop about 2 (still working on the overflow plumbing, it's a non drilled tank)
The pump I picked up is rated at 587 gph at a head height of 5ft

Ok. Assuming your sump is a standard 30gal. 30x12 foot print. And you're able to stop the dt from draining more than 2"

Draining the 2" will equal to approximately 7.5gal + plumbing. I'd say safe to say 8 gals when power is cut.

So in a standard 30gal. You're looking at water level raise of about 5.13"

So on the safe side. You'll need roughly 5.5-6" of head room.

Also with only >600gph going through the sump. There's not need for more than 1-1.25" spacing between the baffles. Water won't be "rushing" between the baffles. So no need for 2" spacing. Space them @ 1" apart to save room in the sump for more equipment

Also height of the baffles should be minimum 16"
Running the sump at a max water level of 12" high (to safely allow the 6" of water back flowing to the sump when power is cut). The baffle height of 16" will allow for good bubble trap, but will allow water to flow over the baffles when power is cut to the main pump.

Does that help?

Sony Xperia Z3

 

[Anthony]

Sorry Eric, I'm still confused,
My 30gal tank is 35.5 wide, 12 deep and 16.5 high,
If my math is right with the tank I'm going to use I will need 4.5" to reserve for backflow issues ( (35.5 x 12 x 4.5 ) /231 =8.3 gal)

 

[EricTMah]

Ya. That's sounds right on your math. So I'd say max water line should be 10" in your sump when running. So I would make your baffles 12" tall. If you go the over under baffle set up. Then the "under baffle will be at 13" high in the sump(with 1" space below it) that will work just fine.

Sony Xperia Z3

 

[Nighthawk26]

Don't forget to allow for excess water from a skimmer with a power outage assuming you will at some point be using one. To one of Eric's points, make sure you consider any siphon from the returns, and for sure how much will drain back via returns and drains.

 

[Anthony]

Hi Guys,
Thanks for the great advice, now that i believe i have the baffle height straightened out, I have another question (sorry the more research i do, the more questions i seem to have)

My original thought was to design my sump with a drain - baffle - refug -3 baffles (i.e bubble trap) - return pattern,
I seem to be coming across a lot more of the drain - 3 baffles - return - 3 baffles - refug pattern (with the drain split to allow water to the drain section and to the refug (drain water in this refug section is limited with a ball valve)

which is a more recommended design,

Thanks again,

 

[4Hummer]

Here is my Setup. First Chamber (On the left) is where the tank drain into. Next is Filter sock, Skimmer, Refuge, bubble trap, Return.

Each section is 1" lower then the previous, (anymore and you get a lot of splashing noise)

As Eric mentioned, ensure you have enough room for the sump to hold all the water from the DT when the pumps shut off, His math is accurate.




Rough Idea on how to silicone the baffles, when doing the bubble trap START WITH THE CENTER ONE.



Here is my build thread. Includes all sump build somewhere

http://reefcentral.com/forums/showthread.php?t=2379295

 

[heath]

nice clear pictures, I use the same method on my tank-sump and it works great...