I hate my overflow

thats disheartening considering i was planning to use CS90's on my two remote tanks i intended to plumb into my existing RR 75gal setup.

i have a U-TUBE style overflow sitting around, but that seemed so much harder to work with than a CPR overflow with lifter pump. let us know how sealing the connection from the lifter pump works. im curious.

as for glasscages.com - i recommend you talk to them and find where the local shipping hub is. i found out mine was only an hour away from my home. it wound up saving me ~$300 in shipping charges.

i went through them for my 75gal reef ready tank. love it. the price was unbeatable. i have seen some negative reviews on them, but the same is said for any other tank company i researched at the time of purchase. this was two years ago, i dont know how they fair today.

 

Er, not really at all. The best style is the U Tube, when built correctly. They don't need a pump, don't ever get air bubbles (which is why you need a pump with the weir-style overflows), and will never lose siphon for any reason. They're simpler, so there's less that can go wrong.

 

I have a u-tube style overflow and don't like it. It does slowly build up air bubbles and if not watched properly, will lose siphon eventually. This is especially true when then begin to grow algae. I have an Eschopps 800 with a Rio 2100 return. I have tried raising the overflow box higher and lower and still eventually get air bubbles. I run carbon in a mesh bag inside the inside box and cover the tube with the mesh so prevent bubbles. I will never buy another tank that is not reef ready.

 

The tube is too wide for the amount of flow if you're getting air bubbles trapped in the top.

 

I kind of figured that and I will try to increase the flow through it. I recently changed out my return plumbing from hard pvc to vinyl tubing. This drastically increased my flow, but the return was too strong for the overflow, so water backed up into my DT. (It's weird b/c I have a Rio 2100, which is rated at 692 gph and my overflow is rated at 800 gph. However, my overflow was unable to keep up with the pump, I don't know why) Since then, I installed a valve on the return tubing that limits the pump. I've gotten an equilibrium but will try to increase the flow rate.

 

i never used the U-tube type. it came with a sump i bought and i had a reef ready tank so i put it to the curb.

looking at it, i dont see how it wouldnt loose siphon during a power outage...

 

I actually was perplexed by this for a couple days until I figured out how the genius who designed an uninterruptable siphon overflow got it to work. I'll type up the explanation. It'll take a minute, cause I need to draw a couple diagrams.

 

indeed, im sitting here with the thing on my desk now starring at it. i dont see how it wouldnt loose siphon. one would think that the amount of pressure from the backflow would cause the U tube to go empty.

edit: humerous that i never even considered this thing till today.... (then again ive been dealing with a reef ready tank or HOB style filtration for the last few years)

 

as for the algae build-up for me this happens maybe once a year, I put dark tape around the top of my u-tube so the light cant penetrate through the clear plastic to grow algae. I never get air bubbles, my u-tube almost touches the bottom of the inside of the overflox box, so that helps. if I do have to clean the internals of the tube and resyphon it I use a airline and suck the 95% air out to get it started again.. once it starts to flow, then I shake the heck out of the tube to get all remaining bubbles out.. then I'm good to go.

 

Ok, so, let me show you how a basic (u tube) overflow was constructed, then the uninterruptable kind. The well designed ones will be uninterruptable, always, just because of their design.

The basic overflow has a siphon that needs to be started manually. In a regular overflow, the siphon will break if water isn't flowing through it. Water from the DT will continue to flow out to the outer box, until the outer box doesn't have enough water to maintain a siphon.


Now, when you add a piece to the equation, you get a water level both on the inner and outer portion of the box that are at the same exact level. You know what happens to a siphon when you get two sides to a tube, both submerged underwater, without air to break the siphon, and the water level is the same on both sides - the water stops moving completely. There's a little extra bit of engineering that goes into this kind of system.




Yes. One piece of plastic, or the length of the U Tube and drain pipe, makes the difference between an uninterruptable overflow and one that will flood your house when the power comes back on from an outage.