Water Flow and Movement in 125

[Tim N Trego]

Ok. I have a 125 (72"x18"x24") and I am thinking of new plumbing and return idea's. I've had the tank for 3yrs and was doing a FOWLR but am considering adding some corals. There is a lot of detirus that accumulates on the liverock with my current set up and wanted to get some feed back on how to change things. I currently have two MagDrive 9.5 as well as 6 powerheads witch I would like to do away with. 3 overflows of the U-tube type feed a 40gal sump below the display tank. The outputs of the two magdrive come directly out of 3/4"PVC pointed towards the two sides of the tank with the 3 overflows spaced across the 3 two foot sections of tank. Should I leave the overflows spaced where they are or try and place them all in the middle 2' section of the tank? I was also thinking of doing a return system found on the following web page ...

http://www.advancedaquarist.com/issues/sept2003/short.htm

Any feed back or ideas would be appreciated. The 3 overflows are plumbed with 1" PVC and handle both Magdrives and could possible handle a third. I have kept frogspawn and hammercoral successfully but lost them during a weeks vacation. Mushrooms are scattered through tank and fish include a Marroon Clown, Blue Tang, Scooter Blenny, and Coral Beauty. Water quality is good with an occsional spike in nitrates.

[ratherbediving]

You can have the overflows wherever you want-- spaced evenly across the back should be fine.

It sounds like you are trying to replace 6 powerheads by adding a return manifold and by possibly adding another (third) return pump. That may work, but using your return pump for all of your water movement needs is going to cause problems.

I think you are going to be more successful by installing a closed loop. I assume you can't drill the tank; Melev on this site has some useful steps for building one,
check out

http://www.melevsreef.com/closedloop.html

For the detailed instructions go to:

http://melevsreef.com/how_to_build.html

[zoomfish1]

Perfect answer. Couldn't have done better myself!!!

[Tim N Trego]

Thanks for the quick reply. I have some thinking to do and just want to gather as much info as I can before coming up with a solution. A Closed loop is what I was thinking and drilling the tank is definately not an option. The next tank will be reef ready and drilled, someday.

[greghigham]

Hmmm... Isn't 72x18x24 a *135g* tank? Just checking, as I am in the planning stage and want to ensure the calculators I am using are accurate! ;)
G

[Tim N Trego]

Could be, I got the tank for free from a guy that was doing away with all but 2 of his tanks. Made a promise to his wife for Valentine's Day and needed to get it out of the house.

[Tim N Trego]

After two days of frustration, I refinished the plumbing on the tank. The three overflows were moved to make room for a closed loop. I now have two MagDrive 9.5 pumps in the sump pumping up to the main tank. At 5 ft they each are pumping about 750 gallons giving me 1500 gallons an hour moving through the sump. I also installed a AquaPro 110 which pumps 900 gallons an hour in a closed loop. I'm not sure how much pressure I loose on pumping the water through the plumbing the pump is rated at 900 gal an hr. I still have to tweak everything but still find the need for powerheads. Two in the front of the tank blowing across the 6 ft front and 2 for surface water movement. Plumbing was incredibly difficult due to the fact I am handicapped by the tank being against a wall and I am getting a small amount of microbubbles from the closed loop occasionally. Two days latter (3 trips to Lowes and 1 to LFS) everything is done. No leaks have been noticed and fish seam happy with the powerheads in.

[ratherbediving]

Sounds good! You can always look at the RC head loss calculator to get an IDEA of how much head loss you are experiencing. The calculator is here:

http://reefcentral.com/calc/hlc2.php

Sounds like your setup is just fine.... but may help explain why your three pumps aren't providing quite enough water movement by themselves.

[Tim N Trego]

Calculator says 580 on the two mag9 giving me 1160GPH and 689 out of the closed loop. The total would be 1849GPH but everything comes out of 45 degree elbows. The PowerHeads are just being used to create surface movement.