2 MagDrive 9.5s ok in a 10g Sump?

[ReefDreamin']

Hey Everyone,

I have attached a sketch of how I'd like to set up my 50g tank and 10g sump. I wanted to put in two SCWD wavemakers and Matt_Wandell (thanks again Matt) suggested I use two pumps instead of just one to get better circulation. With this plan I should get about 20 times the total water volume circulating every hour, which is great, but I'm worried about the force of the pumps being too strong. Each pump has a flow rate of 950 gph at 0 head pressure - is that too much for a 10g sump? If two 9.5s are too powerful to put in a 10g, are there any alternatives I can go with and still get the same circulation? If anyone has any advice, please let me know.

Thanks in advance!

 

[tangir1]

See the following thread for the background info.
http://reefs.org/phpBB2/viewtopic.php?t=49465

 

[ReefDreamin']

Thanks Tangir1

 

[mountainbiker619]

I think two mag 9.5 is to much for the overflow unit. Even one 9.5 is probably to much. What I mean by to much is the mag will be putting more water into the aquarium than the overflow is putting into the sump. So what happins is your sump runs dry.

 

[mountainbiker619]

On another note, I would make sure the overflow intake pipe going to the sump ends below the water line. This way there is no water splashing noise. I would also use a 100 micron sock attached to that pipe to act as your mechanical filtration.

 

[ADS]

If they're submerged consider the heat that they give off in that small volume.
Adam

 

[Ben1]

The limiiting factor is the overflow speed not the size of the sump. The only reason a small sump wont work is if the power goes out and the main aquarium drains a bit lower it might overflow.

 

[LFS42]

I had a 10 gal sump on a 55,
IMO, go bigger with the sump.

 

[Anonymous]

I added this in the other thread...you may just have to add a 2nd overflow, or add a 2nd U tube onto this one. What diameter is the hole in the bottom of the overflow?

 

[elpescado]

To give you an idea of the heat that the larger magdrive pumps give off, one mag 950 heats up a 92gal corner tank by about 5 to 6 degrees F. Multiply that by two and you get a rather warm tank.
A 1" overflow can just handle about 800gph (a little taxing on it, but it can handle it). I would do 2 drain outlets and one bifurcated (forked) return pipe. Instead of using two mag 950's use a mag 1200 and run it as an external pump (meaning you would have to have your sump drilled on the end down near the bottom and instal a 3/4 threaded bulkhead fitting). Running it as an external pump would reduce the heat factor.
You can still use the SCWD units by setting up an external recirculating pump (from the tank to the pump to the tank, bypassing the sump alltogether).
Whatever you do, try to keep large magdrive pumps out of the water as they heat things up rather quickly.

 

[mountainbiker619]

I would check out the new quiet one pumps. I purchased one for my 60 as the return pump and very very quiet and little heat transfer.

 

[ReefDreamin']

Wow, thanks for all the great advice guys...there were a lot of things pointed out that I hadn't even considered, especially the heat output of the pumps (eek!). I have made some revisions to my dual SCWD sketch, keeping all your ideas in mind.

I figured I'd upgrade to a 25g sump and use an external pump to avoid overheating the water, and go with 2 overflows to make sure everything is balanced out. This sketch shows a non-drilled sump option. I figured it would be less complicated, although I hope I don't kick myself for it later. :wink:

This set up leaves me with plenty of room in my sump for the skimmer and heaters, and maybe even a refugium. I don't know whether to go with the MagDrive 12 or 18...and if a MagDrive is even the best choice here. On the MarineDepot website it says not to use the MDs externally. Is there any reason for this?

Thanks again for all the help so far...any additional advice you have would be much appreciated!!!

 

[Steven]

Your diagram shows the Magdrive above the sump. I don't think these pumps can suck water up out of the sump. I believe they need to be below the water line to work. Better check with the manufacturer first.

 

[ReefDreamin']

Oooooooohh....good point. Didn't think of that. Would this work instead?

 

[Eryl Flynn]

For your design you need an overflow or to drill a hole in the sump for the pump. The pump won't pull the water out and over the wall of the sump.

I suggest drilling a hole and putting in a bulk head, then connecting the pump to that.

 

[Anonymous]

I had a 10 gal sump on a 55,
IMO, go bigger with the sump.

Yeah.. I'd go with a larger sump as well.. especially if you are going to put in *two* pumps, later on down the road you may want to put in a "in-sump" skimmer, and you won't have the room... bigger is better with sumps. IMHO,
~wings~

 

[ufans]

Why not just keep the pump inside the sump? That is the simplest. It reduces the chances of leaks at the connection points to the pump and reduces the stress of the pump intake so it is just pushing water and not trying to pull it.

Lastly, you better consider the pressure on the pipes between the pump and the wavemakers. It can be significant if both wavemakers are closed. No telling what that is going to do to the pump over time since it will be under quite a bit of stress.

You sure are pushing a lot of water... I wish you luck.

 

[Anonymous]

If you do it external, go with a bulkhead drilled through the side of the sump. It's also important to plan ahead for when you have to service your pump. Most folks put a ball valve and threaded union on both sides of the pump in able to get the pump out for any repairs w/o having to drain the tank. I also put an elbow facing down inside the sump to prevent creating a little whirlpool. I wish I had a pic of this, or a diagram.

 

[Ben1]

As long as the water line is primed before you plug in the pump you can use like in diagram 2. The problem as I see it in both diaghrams is if you didn't use check valves, a power outage would cuase the pump to run dry.

Of course the only two fail safe methods would be keep it in the sump or as Matt already said use a bulkhead in the sump and get it drilled. If your handy with a dremel use a glass bit to try to drill it. A glass 10 so cheap its better to try yourself. If you go with a bigger sump don't do it yourself.

FWIW, I use a mag 9.5 and a sen 900 for returns in a 20 gallon sump under my 150. I dont have heat problems or miss the space in the smp as my skimmer runs externally. I have a Mak 4 running a Bullet 3 which is plumbed just like your first diagram with the pump pulling water up from the sump. I use a check valve in the line to keep it from running dry but that isn't always 100% safe.

 

[Anonymous]

Check valves will eventually fail in a SW aquarium. They get coated with sponges, feather dusters, etc. and stick.

If you do use a 10 gallon and want to drill it, there's a very simple way to do it w/o buying expensive glass drill bits. Take a razor blade, cut out the silicone around one of the small panes. Push it in and remove it. Go down to your local hardware store, and get a piece of 1/4" thick acrylic. Have it cut to the exact size of the glass pane you just removed. Also, have them drill a hole of the approriate size w/ a hole saw. It's much easier to drill acrylic than glass. Just use a high RPM drill, low pressure. Then you can silicone in the piece of acrylic to the bracing of the tank. It works, and it's easy! (Plus if you screw up it's only $10 )

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