overflow boxes

[rossv]

im wanting to buy an overflow box to get water to my refugeum.... i was thinking about gettin this one

http://www.marinedepot.com/md_viewIt...product=CR1511

could u guys explain to me how it works? it comes with everything i need right? how does the continuous siphon work?

ty muchly

ross

[loganj]

CPR overflows rely on a powerhead to keep the air out of the siphon. This doesn't mean the water will hit the floor if the [acronym:04b2945aa7="Powerhead"]PH[/acronym:04b2945aa7] quits though. You'll need a [acronym:04b2945aa7="Powerhead"]PH[/acronym:04b2945aa7] to attach to the air line fitting on the overflow tube. I would suggest at least a Maxi Jet 900. The air line runs from the overflow tube to the venturi attachment on the [acronym:04b2945aa7="Powerhead"]PH[/acronym:04b2945aa7]. The idea is that the suction from the venturi will clear any air bubbles that find their way into the tube. A strong [acronym:04b2945aa7="Powerhead"]PH[/acronym:04b2945aa7] will even restart the siphon by itself. Personally, I like the old U tube overflows. I have had good service from them. You'll want to make sure that the air line going to the [acronym:04b2945aa7="Powerhead"]PH[/acronym:04b2945aa7] is submerged even when the pump is shut off and the water level in the main tank drops. One thing to note: if the air line ever comes off, the siphon will break and the tank will overflow.

[fishfreek]

Im a firm beliver in the U tube overflows vs the CPR style overflows for the exact reason logan explained in their need for a [acronym:f1db76d46b="Powerhead"]PH[/acronym:f1db76d46b] to help keep the overflow free of air. U tube overflows dont have this problem usually and if they do then its usually a result of to low of flow going thru them.

Most single U tube overflows will be able to handle approx 600-700GPH flow rate. Hara found some nice U tube overflows on ebay or you could look at www.lifereef.com for their prefilter box's.

[scuba_steve]

also not only do ya need to buy the powerhead but the venturi as well forget were i found mine !! the only up side is that cprs take up less room in the tank

[loganj]

All the Maxi Jet [acronym:353b3e6053="Powerhead"]PH[/acronym:353b3e6053]'s come with the venturi attachment. I wouldn't trust anything else. I know you all get tired of me talking about Maxi Jet [acronym:353b3e6053="Powerhead"]PH[/acronym:353b3e6053]'s, but they really are that good.

[scuba_steve]

no they dont !! ya need the part that plugs into the input side of the pump and the air line attaches to !! just like the seaclones come with !! if it does come with that then ive bought 8 of them and none had it in the box mabe i have mine set up diff ?!?! but that how mine is set up !! ahhhhhh i think i got it ya sticking the air line to the tip ??? i bought the attachment for the air line to sit before the impeller !! if your using the tip the [acronym:8219b9c234="Measure of the concentration of hydrogen ions"]ph[/acronym:8219b9c234] came with how well does it work if ya sump is over 12" deep ??? my way seams to suck no matter how deep !! follow me ?? learned something new
http://www.premiumaquatics.com/Merch...y_Code=Maxijet


this is what i thought ya had to use so i bought 2 for both my overflows

[loganj]

On a MJ900 or 1200, the attachment that comes with the [acronym:e2efa8888b="Powerhead"]PH[/acronym:e2efa8888b] is sufficient to keep the air out of the overflow. It does attach to the output side of the [acronym:e2efa8888b="Powerhead"]PH[/acronym:e2efa8888b]. The 1200 will even reprime the siphon tube if installed that way. I wouldn't recommend this option with either the 600 or 400 as they don't generate enough flow. The powerhead should be located close to the surface and inside the main tank. Even if you use the other attachment, the MJ venturi available from Premium Aquatics, you'll lose flow as the [acronym:e2efa8888b="Powerhead"]PH[/acronym:e2efa8888b] is moved deeper. Although this attachment will work fine, it is not needed for this application. It is primarily intended for use with smaller skimmers that use the MJ as a pump. The depth of the sump has nothing to do with keeping the air out of the overflows.

[Biggen]

Go with the advice Logan and fishfreek gave you. I have a CPR overflow, but if I had to do it again, I would get the "U" type. It has never given me any problems but it is just something else that "could" go wrong even though it probably never will.

[scuba_steve]

cool didnt know that that would work !! but if ya have the [acronym:b26407a0bc="Measure of the concentration of hydrogen ions"]ph[/acronym:b26407a0bc] in the main tank god i hate to see all the air it pushs thru it ughhhh

i had to wait a week to get that little piece before i good get set up lololol to to funny

[wseaton]

LoganJ called it. Go U-tube.