supply vs return

[dillonsshop]

can anybody help, after setting up my tank, I find that return is faster than the overflow to my wet/dry can supply. I've already put a bal valve in the return line but it must be adjusted every couple hours to keep from overflowing either the tank or the filter.

[Texreefer]

only two solutions IMO.. either smaller return pump,(easiest) or larger overflow ( more complicated depending on what type of overflow you have

[caferacermike]

I agree with Mike. Do what you can to match them better. There is no point running a pump larger than you can handle. This not only wears out a more expensive pump but also uses unnecessary electricity. Adding a ball valve puts back pressure upon the pump's impeller and seals. If you can, cut a TEE into the line above the pump and add a 90 to that so it points back down. Then add your ball valve and let the water pour back into the sump. You can regulate your flow into the tank and let the pump run full steam. This will recirculate the "excess" into the sump.

[dillonsshop]

I agree with Mike. Do what you can to match them better. There is no point running a pump larger than you can handle. This not only wears out a more expensive pump but also uses unnecessary electricity. Adding a ball valve puts back pressure upon the pump's impeller and seals. If you can, cut a TEE into the line above the pump and add a 90 to that so it points back down. Then add your ball valve and let the water pour back into the sump. You can regulate your flow into the tank and let the pump run full steam. This will recirculate the "excess" into the sump.

this is an external pump(dry)??? so if I have 1" return line what size do you recomend to put back into my wet/dry?

[dillonsshop]

sombody also told me today that I could put a rheostagt on the power line and vary the pawer that I supply to the pump. Any comments?

[Texreefer]

sombody also told me today that I could put a rheostagt on the power line and vary the pawer that I supply to the pump. Any comments?

My question would be Why? stick with whats proven and what works,,, your best and easiest fix is find out what type of overflow (whether built in or hang on) and what GPH it can handle and get a pump that meets (but does not exceed) that rating.

[dillonsshop]

I'm not sure the brand or rating of either, as they came as a USED package. I will get the info I have tonight , but I think the return to the supply side of the pump is the way I'll go. Still want to know what size is recomended comming off a 1" return line, 1/2???

[brewercm]

This info could really help everyone out in trying to help you. What pump are you using for your return, and what size and how many lines to your sump. The return line from your pump back to your tank means very little unless you have it way undersized and it's building a lot of back pressure.

[caferacermike]

It's all relative to your set up as to what size suction line to run. If your tank is set up for a 1" bulkhead you are not going to be able to get it to flow much better than that. You can try to uspize it to 1 1/4" but you will still have the obstructed flow through the bulkhead. Just because your return pump has a 1" outlet does not mean that it produces a lot of GPH. You are measuring how much mass you can force through the pump, until you figure out what pump it is, it will be difficult to say anything about it. I could just as easily design a 400GPH return pump with a 1" outlet just because I could. Could you at least tell us what color it is? Blue/ Iwasaki, Yellow/Panworld, Black/Sequence or Ampmaster perhaps? What size tank is it? That could give a better idea if the pump is to large, small for the tank. Is the overflow built into the tank (IE: Reef Ready) or is it a hang on tank style? If it's a HOT how many pipes come from it? 1 is rated for 6-700GPH 2x 1,200 or so GPH.

I would never run a rheostat on a pump. Lowering the amperage being delivered to the windings could easily cause it to overheat melting the windings or worse yet, catching fire. Electric motors are generally built to run at one speed unless it is a purpose built motor. The only motor I know of in the hobby that can actually handle this are those used by Sequence on the Dart and Snapper pumps. They can be throttled back with a ball valve and this will slow the motor.

[Bill S]

As noted above, post what you have, maybe with a couple of pix. You also need to consider what happens if one of your drains blocks, or what happens when the electricity goes off. If either of those questions results in a water spill, you need to re-engineer. Personally, I make SURE my drains are at least 2x what the return will pump. That way, if a snail lodges in the return, I don't have a mess. 'Cause a snail WILL eventually get stuck.

[jc]

Another benefit with going with a smaller pump is less heat getting into the tank.

[GeoB]

First things first, if your filter overflows, you need to remove water from the system. You want your sump (filter) to be able to handle all of the overflow when your return pump is turned off. Turn your pump off and watch the water level in the filter, if it looks like it is going overflow, turn the pump back on. Remove water from the system and try again. Since your pump and your overflow are mismatched, your pump might start pulling air during this process, but keep going until the filter can handle all of the overflow when the pump is turned off. Once the filter can handle all of the overflow that you get when the return pump is off, do not add anymore water to the system until you have the return vs. overflow problem fixed (turn off the auto topoff if you have one).

Once you have the right amount of water in the system, the easiest thing to do would be to get a smaller pump. Use the Reef Central Overflow/Drain Size calculator to determine how much overflow your system can handle, then buy a pump accordingly. If you want to keep your current pump, the first thing I would do is maximize the overflow rate by eliminating any elbows by using flex pvc. Using piping that is a size larger than the bulkheads might help some. Next I would use the tee method to regulate pump flow that was recommended earlier.

Just remember during this process that if you start with a full sump (filter) when you turn the pump on and the pump starts to run dry, do not add more water. Turn the pump off and then do something to increase the overflow rate or reduce the pump flow rate, and try again. I had to learn this lesson more than once.

[caferacermike]

Buying the right sized sump is tantamount to not having to go through the above headache. Instead of worrying about all that I use a formula to dictate the size of my sump, not my pumps. By multiplying your show tank's length x width x 4" this will generally provide enough "back up space" in your sump so that in the event of a power failure you will not have to worry about overfilling your sump. Increase the size of the sump by what you find and how much sump you wanted. Example. My tank is a standard 75g. 48" x 18" = 864sqinches of surface area. 864 sq" x 4" of "oops space" = 3,456 cubic inches of volume. 3,456 cubic inches x 0.00433 (the conversion)= 14.96 or 15 US gallons. After all that takes place I knew I wanted at least 20g of water in my sump. I had a custom made sump that could handle 40g of water but only has about 20g running through it. This allows for an electric outage or any other sort of catastrophe to be averted. The next step is to drill a 3/32" hole about 1/2" below the water line in the return piping headed to the show tank. This prevents more than 1/2" of tank depth (or 48"x18"x0.5"x0.00433= 1.87g of water) back siphoning. By placing my durso standpipe near the the height of my overflows this also helps prevent draining the water that would normally be in the overflow. All in all when I lose power I actually only lose about 3g of water to my sump. That leaves about 17g of extra insurance to prevent a flooded home.

I could never actually lose 4" of depth from my tank as I don't extend any piece of my plumbing more than 2" below the water line as another form of insurance, but sure is nice going to work everyday knowing that I will never have a flooded home. Plus I've never spent more than 10 minutes setting up a pump to a new tank.

[caferacermike]

Oh and by properly matching your pump to your system it truly is "plug and play" at that point. I use an Eheim 1262 return pump rated for 900GPH at 12' head, running 3/4" return and a 1" suction. I've never had to adjust anything.

[dillonsshop]

what I have is 110g tank with a 10-11g wet-dry filter. The return pump is a "Little Giant" model 3-MDQX-SC rated at 1100gph. The filter is a CPR and so is the overflow. The overflow has 1" ID spa tubing leading to the wet-dry filter. The sump then has a 1" bulkhead fitting that leads to the pump inlet and then a 1" ball valve on the output side of the pump then 1" ID vinyl tubing that splits into two (left and right) that becomes PVC at the edge of the tank and goe into the tank. I've got holes drilled just below the water line so that in the event there is a power failure the return does not siphon water back into the sump and overflow the system. I think that the sugestion @ branching off the return line back to the sump with a ball valve will help alot, but I still don't know if the pump is way too much or just rite or what. Also still not sure what size the return to the sump pipe should be.... I'm thinking @ 1/2 or 3/8 pvc. Thanks for all the info so far, I could not have gotten this far without this site and all the members that contribute.

[caferacermike]

Also still not sure what size the return to the sump pipe should be.... I'm thinking @ 1/2 or 3/8 pvc.


This line has confused me in your thread before. You just mentioned that you have 1" spaflex coming from your overflow to the wet/dry and then you run 1" back to the tank and "TEE" it off to 2 smaller nozzles. This is typical and should work very close to the pump you have. I'd bet the Little Giant boasts a bit and you would have closer to 900GPH a the tank. However I'm stumped by your query of "return to the sump pipe". Are referencing my idea of a recirculating loop to the sump? If so a 1" TEE would work well. Then 1" pipe it around so it points back down and add a 1" ball valve to the drop piece and a short piece of PVC lower than the water in the sump so you don't hear it splash. You could probably use a 1x1x1/2" and 1/2" PVC if you wanted.

I'll draw something up for you. It'll take me about 30 minutes.

[caferacermike]

http://i53.photobucket.com/albums/g48/caferacermike/recircbypass.jpg

Hope that explains it a bit better than my lack of typing skills. Just regulate how much "dump" you need into the sump with the valve, open and close it until you see your speeds match up better.

[Bill S]

I'd sure make sure that your TANK will hold the contents of your sump without overflowing. Reliance on a single drain is never a good idea...

[dillonsshop]

here are some pics of the setup as it is now, I'll modify according to Mike's recomendiations this weekend and post new pics after......unless something else goes terribly wrong. BTW, your drawing helped ALOT Thanks.

[dillonsshop]

the pics are too big, I'll take some at a lower resolution to see if that makes a diference.

[erikharrison]

google microsoft image resize tool. After you install it, just select whatever files you want to resize, and select "resize images". Super fast and saves a ton of time.

[dillonsshop]

here are the pics....

[dillonsshop]

here are the rest of the pics resizer works great!!

[erikharrison]

Looks like Mike's diagram was spot on! You should only have to tinker with the flow to get it adjusted to where it needs to be! Then you can crank on that skimmer and adjust it as well! When you get up and running, make sure you keep topping off your water daily to the same spot since you will have your skimmer adjusted for it!

[dillonsshop]

I just need a few hours to work on it uninterupted and a few drinks and everything should be just fine!

[erikharrison]

Make sure it's only a few drinks. More than a few = flood! :rofl: