Tank level, sump level, pump question

eastfernstreet · 02/12/2013, 10:43 AM

I've had my 90 gallon with drilled out off-center overflow and nearly 20 gallon sump up and running for a few months now. Livestock happy, etc.

I've never, however, been able to have the tank completely full because if I fill the display tank to the top, my sump becomes too full. I need to keep an inch or two of empty space at the top of the tank.

My theory is that my return pump is too weak and that when the tank is full, too much water enters the overflow and overwhelms my pump's ability to return it to the tank. Is this likely? I've considered putting a valve on the return line to slow it down, but fear that it could result in a DT overflow and MUCH trouble with my spouse.

If I get a stronger pump, do I not also run the risk of a DT overflow?

My brain hurts from trying to visualize the alternatives and I'd greatly appreciate any guidance.

theatrus · 02/12/2013, 10:51 AM

The water level in your display tank is set by the overflow height (+ some fudge factor for actual water flow). Is there anything you can adjust? What type of overflow is it?

If you replace your return pump with something much stronger, and your overflow gets slightly clogged with algae or other junk, you run the risk of overflowing the display. You want lots of extra capacity on the drain lines.

Palting · 02/12/2013, 11:04 AM

The water level in the DT has little to do with the return pump power. It has mostly to do with the height of the overflow box. If you want your DT water level higher, you have to raise the overflow box somehow.

The maximum gph you can have for a return pump is determined by the capacity of your overflow. Most drilled overflows usually start at a capacity of about 700gph, and larger ones can go 1400gph. Bear in mind that the actual GPH of the return pump I significantly decreased by head height. So long as your return pump GPH stays just below the overflow capacity, there should be negligible risk of overflowing the DT. Unless the overflow clogs with a snail or algae.

eastfernstreet · 02/12/2013, 11:49 AM

Quote:

Originally Posted by theatrus

The water level in your display tank is set by the overflow height (+ some fudge factor for actual water flow). Is there anything you can adjust? What type of overflow is it?

It's one of those double layered black plastic box overflows that's affixed to the tank with sealant. If there's a way to adjust it, I haven't found it. That was my original solution -- if the top, perforated part were raised an inch it would solve the problem. Surely others have faced this issue?

eastfernstreet · 02/12/2013, 11:53 AM

Quote:

Originally Posted by Palting

The water level in the DT has little to do with the return pump power. It has mostly to do with the height of the overflow box. If you want your DT water level higher, you have to raise the overflow box somehow.

That's what I thought, but there doesn't seem to be a way to do that. These overflows seem pretty standard on the manufactured tanks I've seen. All sealed tightly in place to the back of the tank. Any "tricks of the trade" to raise the overflow height without actually being able to move it?

Palting · 02/12/2013, 12:19 PM

So, I'm guessing this is one of those commercially made Reef-Ready tanks? Unusual for the water level to be that low in that case. Is the water level below the trim so you can see it?

Thought I'm surprised you have to do this if that's the case, but one way is to get some acrylic from Lowe's or Home Depot. Cut it to size and shape, cut some notches for teetch, then glue it to the overflow box so that it raises the water level the height you want to. If you're only raising it an ich, and since I'm assuming this is the overflow box simillar to aqueon or marineland tanks, just get a thin type of acrylic so you can easily bend it around the box. The drain tubes can stay the same, but if the returns come up the box and over the top, you may have to extend the return tubes a simillar mount.

eastfernstreet · 02/12/2013, 01:09 PM

Quote:

Originally Posted by Palting

So, I'm guessing this is one of those commercially made Reef-Ready tanks? Unusual for the water level to be that low in that case. Is the water level below the trim so you can see it?

You guessed right. The water level is just barely below the trim -- just enough to bug me every time I look at it but not enough to be a huge issue.

Quote:

Originally Posted by Palting

Thought I'm surprised you have to do this if that's the case, but one way is to get some acrylic from Lowe's or Home Depot. Cut it to size and shape, cut some notches for teetch, then glue it to the overflow box so that it raises the water level the height you want to. If you're only raising it an ich, and since I'm assuming this is the overflow box simillar to aqueon or marineland tanks, just get a thin type of acrylic so you can easily bend it around the box. The drain tubes can stay the same, but if the returns come up the box and over the top, you may have to extend the return tubes a simillar mount.

Thanks. I think I'll have to try some such kind of "mod" job. I just wasn't sure if perhaps the issue was more equipment-related (like my pump was too weak or some such -- I am a noob, after all.)

Off to Home Depot I go! Thanks again.

Palting · 02/12/2013, 01:29 PM

I just had a thought. I'm still stuck on the improbability of a too low overflow level in a commercially made RR tank

. Especially since I have 2 of them currently. Is the water level vsisble all around the trim, or is it only in front? If it's only in front, it may be that the tank is sitting uneven and is tilted towards the back.

eastfernstreet · 02/12/2013, 02:17 PM

Quote:

Originally Posted by Palting

I just had a thought. I'm still stuck on the improbability of a too low overflow level in a commercially made RR tank

. Especially since I have 2 of them currently. Is the water level vsisble all around the trim, or is it only in front? If it's only in front, it may be that the tank is sitting uneven and is tilted towards the back.

Sadly(?) the tank is level and the light leaks from all sides. Cool to know that you're still thinking about it.

I'm figuring that the factory must, at least once in a while, glue the overflow a half inch lower than it should be. I'm just always jealous of the tank shots in which the water level is right up to the top.

I've considered some heavy duty tape along the bottom 1/2 inch of the grating but am fearful of the chemicals in the adhesive. Thoughts?

02/12/2013, 10:43 AM	#1
eastfernstreet Registered Member Join Date: Oct 2012 Location: Tampa, Florida Posts: 150	Tank level, sump level, pump question I've had my 90 gallon with drilled out off-center overflow and nearly 20 gallon sump up and running for a few months now. Livestock happy, etc. I've never, however, been able to have the tank completely full because if I fill the display tank to the top, my sump becomes too full. I need to keep an inch or two of empty space at the top of the tank. My theory is that my return pump is too weak and that when the tank is full, too much water enters the overflow and overwhelms my pump's ability to return it to the tank. Is this likely? I've considered putting a valve on the return line to slow it down, but fear that it could result in a DT overflow and MUCH trouble with my spouse. If I get a stronger pump, do I not also run the risk of a DT overflow? My brain hurts from trying to visualize the alternatives and I'd greatly appreciate any guidance. __________________ Learning Patience In hobby since 09/12. Current Tank Info: 90 gal., 2 2x54w T5 w/ATI's, 100+ lbs. LR, 125 Coralife SuperSkimmer, 2x Maxspect Gyre XF250, 2 O. Clowns, 1 Longnosed Hawk, 1 Tomini Tang, 1 Flame Angel, 1 Green Mandarin, Rics, Fox, Montis, GSP, Zoas, Gorg, Birdsnest, Shrooms, Shrimp, Crabs, etc.

02/12/2013, 10:51 AM	#2
theatrus 100-mile-commuter Join Date: Dec 2004 Location: almost nevada Posts: 4,721	The water level in your display tank is set by the overflow height (+ some fudge factor for actual water flow). Is there anything you can adjust? What type of overflow is it? If you replace your return pump with something much stronger, and your overflow gets slightly clogged with algae or other junk, you run the risk of overflowing the display. You want lots of extra capacity on the drain lines. __________________ Custom electronics purveyor. blueAcro.com Current Tank Info: 90g SPS+mixed reef (10 yrs): LEDBrick LEDs, 40g custom sump, Ca reactor, chiller, Vortech, lots of custom electronics

02/12/2013, 11:04 AM	#3
Palting Registered Member Join Date: Apr 2010 Location: Ohio Posts: 6,912	The water level in the DT has little to do with the return pump power. It has mostly to do with the height of the overflow box. If you want your DT water level higher, you have to raise the overflow box somehow. The maximum gph you can have for a return pump is determined by the capacity of your overflow. Most drilled overflows usually start at a capacity of about 700gph, and larger ones can go 1400gph. Bear in mind that the actual GPH of the return pump I significantly decreased by head height. So long as your return pump GPH stays just below the overflow capacity, there should be negligible risk of overflowing the DT. Unless the overflow clogs with a snail or algae. __________________ Anything I post is just an opinion. One of many in this hobby. Believe and follow at your own risk of rapid and complete annihilation of all life in your tank :) Current Tank Info: Incept 3/2010, 150 RR, 50g sump, 20g fuge, 150w 15K MH x3, T5 actinics x8, moonlight LED x6, 1400gph return, Koralia 1400 x4, 300 g skimmer, 4 tangs, 2 mandarins, 2 perc, 6 line, 3 cardinals, 2 firefish, SPS, LPS, zoas, palys, shrooms, clam

02/12/2013, 12:19 PM	#6
Palting Registered Member Join Date: Apr 2010 Location: Ohio Posts: 6,912	So, I'm guessing this is one of those commercially made Reef-Ready tanks? Unusual for the water level to be that low in that case. Is the water level below the trim so you can see it? Thought I'm surprised you have to do this if that's the case, but one way is to get some acrylic from Lowe's or Home Depot. Cut it to size and shape, cut some notches for teetch, then glue it to the overflow box so that it raises the water level the height you want to. If you're only raising it an ich, and since I'm assuming this is the overflow box simillar to aqueon or marineland tanks, just get a thin type of acrylic so you can easily bend it around the box. The drain tubes can stay the same, but if the returns come up the box and over the top, you may have to extend the return tubes a simillar mount. __________________ Anything I post is just an opinion. One of many in this hobby. Believe and follow at your own risk of rapid and complete annihilation of all life in your tank :) Current Tank Info: Incept 3/2010, 150 RR, 50g sump, 20g fuge, 150w 15K MH x3, T5 actinics x8, moonlight LED x6, 1400gph return, Koralia 1400 x4, 300 g skimmer, 4 tangs, 2 mandarins, 2 perc, 6 line, 3 cardinals, 2 firefish, SPS, LPS, zoas, palys, shrooms, clam Last edited by Palting; 02/12/2013 at 12:27 PM.

02/12/2013, 01:29 PM	#8
Palting Registered Member Join Date: Apr 2010 Location: Ohio Posts: 6,912	I just had a thought. I'm still stuck on the improbability of a too low overflow level in a commercially made RR tank . Especially since I have 2 of them currently. Is the water level vsisble all around the trim, or is it only in front? If it's only in front, it may be that the tank is sitting uneven and is tilted towards the back. __________________ Anything I post is just an opinion. One of many in this hobby. Believe and follow at your own risk of rapid and complete annihilation of all life in your tank :) Current Tank Info: Incept 3/2010, 150 RR, 50g sump, 20g fuge, 150w 15K MH x3, T5 actinics x8, moonlight LED x6, 1400gph return, Koralia 1400 x4, 300 g skimmer, 4 tangs, 2 mandarins, 2 perc, 6 line, 3 cardinals, 2 firefish, SPS, LPS, zoas, palys, shrooms, clam