Plumbing help, DT overflows - Page 2

motorslave · 07-20-2008, 05:29 PM

At this point the only thing I can think of is to change the way the you are connected and move the mantis tank. Split the return from the sump and have each one overflow to the sump independently. They will only overflow what is pumped to them so balancing the flow wouldn't be too difficult. That's the simple way. Otherwise you may be fighting this for some time.
Maybe some one will have a better idea but I think the way that is set up is just not mechanically sound for what you intended it to do.

PEMfish · 07-20-2008, 06:04 PM

The Mantis tank is unmovable. Besides, that won't fix the problem. Even with a fall water is not flowing like it should.
But thank you for the suggestion.

motorslave · 07-20-2008, 07:16 PM

Quote:

Originally Posted by PEMfish

The Mantis tank is unmovable. Besides, that won't fix the problem. Even with a fall water is not flowing like it should.
But thank you for the suggestion.

Its all n how you plumb it to take advantage of gravity. Ive dealt with somewhat similar issues before so yeah it can. But with the tank un move able that scratches that.

Plaz · 07-20-2008, 07:37 PM

OK, so you need either more or fatter connections between your DT and the mantis tank. Can you drill more holes to connect the two tanks? If so, put a 1-1/2 ID bulkhead between them (deeper so it is always fully submerged) and it should work. With less than 2" of differential head pressure through single bulkhead, I don't think it can support a 266GPH flow rate.

Otherwise, Motorslave's idea is probably your best bet. Split the flow so you have less going to the DT. Might not give you the turnover you're looking for, though.

Seamore · 07-20-2008, 08:18 PM

how about a HOT overflow in te DT to handle the excess flow back to the sump? then you could crank it up

PEMfish · 07-20-2008, 10:46 PM

I like those ideas. I think I will have to put in a bulkhead lower in the tank. ****, I will have to drain it. Dose everyone agree with doing this?

motorslave · 07-20-2008, 10:55 PM

If youre going to add a bulkhead you dont have to drain it all the way. Drain down to a level below the placement of the BH. (give yourself room to work) Take a Hefty bag and tape it to the side of the tank below where you will be drilling. This will catch debris. When you are ready to remove it be especially carefull to make sure you get all the debrisalong the area you tape. Also you make sure to use a tape that will not leave a residue behind. Packing tape is a good one.

motorslave · 07-20-2008, 10:59 PM

Putting a bulkhead lower in the tank will esentially make one tank if the BH is below the water level in the mantis tank and you will have even more problems when the two tanks equalize. The DT tank will drop and the mantis tank will want to rise.
Can you get some better pictures showing the back of the DT and the distance betwen the two water levels?

PEMfish · 07-20-2008, 11:31 PM

I can control the water level in the mantis tank by changing out the pipe in the stand pipe. If I do add a BH I will plumb it up like this;

motorslave · 07-20-2008, 11:37 PM

Okay, I was thinking the top of the mantis tank was lower than the display. If they are the same then no issues. Basically your just making it one tank in effect.

motorslave · 07-20-2008, 11:38 PM

But still, the two will equalize levels so you control the level in one then it effects the other.

PEMfish · 07-21-2008, 12:05 AM

Really, did you look at the pic?

motorslave · 07-21-2008, 12:16 AM

Yeah but didnt really see the size of the mantis till you posted the scetch. With two bulkheads, one lower than the other, the water level in the two tanks will act as if its just one tank. Do you follow me? if you only have to one drain in the mantis tank then you may need more thanone more bulkhead. Water wont flow through at the same rate as if it were pumped or even gravity flowing.

Plaz · 07-21-2008, 12:56 AM

You shouldn't need to go that deep in the display tank for your connection. If I remember my physics properly, the flow rate though a connection is related to the diameter of the connection and the difference in water levels between the two tanks, not the absolute depth of the opening. With the inverted U at the top of the DT, I think you're also limiting the flow a bit.

From the pic, it looks like you are preventing water from backflowing into the DT from the mantis tank as long as the standpipe is set low enough. Looks OK to me.

I think I would still go deep enough to make sure the water feeds below the water line in the Mantis Tank to avoid too much splashing. If you're going to do the inverted U thing to keep the mantis tank at a lower level, then you definitely want a larger diameter pipe and you might need a way to let air in/out of the top of the U. I've also seen it done with T's as well. If you get the tube large enough and the air flow figured out, then it can flow pretty nicely without too many bubbles.

PEMfish · 07-21-2008, 10:23 AM

So your saying that I should just let the BHs sit open to get the two tanks to act as one? Sounds good to me. But will it affect the twin? There is the exact same thing next to the mantis tank, its a fuge. But its drain goes right back into the DT with an inline pump. ( see pics ) Should I Open it up to?

Bact to topic; Should I try taking off the plumbing on the BH and see how that works? I would have to break it it off but with luck it will break on the connections, witch is reparable if this don't work out. I think thats my best bet right now.

This frits pics is very old, I didn't even have the stand for it built yet but its the same system so it works