overflow box question

[madugo]

i am trying to set up the wet dry...
the tank is not rr so need a overflow...
i am gonna go with cpr overflow...but kinda dont know which one to match the pump...
the pump does 1200gph, but the headheight is 5 feet, so it should only pump out 800gph according to the chart of the pump...
the wet dry is only for a single bulk head, but i have 2 socks, which i think i can do a dual overflow, just run 2 hose, and tie the other one to the sump..
they have a dual overflow that is for 1200gph, with 1" bulkheads.
or they have a 800gph single overflow or even a 1600gph single with 1.5 inch bulkhead..should i go with that? the price of all three of them is not much different.
would a 1600gph single be better? or i have to match the gph of the overflow with the gph the pump deliver?
thanks all.

[imagirlgeek]

You want the overflow box to be able to flow more than the pump you are using. The only problem you'd ever run into is if the pump was pumping water faster than it could flow through the overflow box back down to the sump.

Only the water in the tank that rises above the lip of the overflow box can flow down to the sump. If the pump is fast, then more water will flow over the lip, into the overflow box, and down to the sump. If the pump is slow, then less water will flow over the lip, into the overflow box, and down to the sump.

Fast pump --> slow overflow = too much water returning to the main tank and potential for overflowing the main tank.

Slow pump --> fast overflow = water from main tank must get over the lip of the overflow in order to flow to the sump, so only the water returned to the tank via the pump contributes to the water level going over the lip of the overflow box to flow to the sump.

So if the pump moves water faster than it can flow through the overflow, the water level in the main tank would rise until it overflowed the tank. This is why the overflow box should never have a lower flow rate than the pump.

Make sense? It's hard to put it into words.

[Zulaab]

Having looked at the CPR units, I like them and I would run one or two of them.
If I was you, I would get the 1.5" units, then reduce it down into the fitting on the wet/dry. What size wet/dry you running ? Home made ? Or brand name ?

Pictures helps !

[myjohnson]

madugo,

I'm assuming you have a mag 12 that pushes1200gph. Like Traci said, you don't have to match the pump rating to the overflow rating. You just have to make sure the overflow rating is higher than the pump rating.

This is the odd thing that happened to me. I got a mag 12 and a dual overflow with 1" bulkheads so I thought that would be fine. I have about 4'' headheight so the pump can not being doing 1200gph.

However, when I hooked everything up the pump was moving too much water for my overflow box. I had to buy a PVC ball value and install that between the return line to lower the flow.

So I actually think the standard flow rate from a mag 12 is either a little more than 1200gph or the standard flow rate from a overflow box with two 1'' bulkhead is lower than 1200gph. Either way the PVC ball value allowed me to lower my flow rate and find the balance that I wanted. You might want to look to getting one. They are like 3 bucks at any hardware store.

Good luck with your system man. Call me if you need any help.

[Matt in Houston]

I have the CPR CS202, which is probably the dual one you are speaking of...It works great and is VERY quiet once you mess around and move the hoses in the right spot. Keep in mind the flow rates are advertised with no sponge prefilter or screen in place. If you have small fish like tetras sized, they will fall into it if you dont use the screen...and even some very small fish can slip thru the holes in the screen.

I dont think you can go wrong with either the CS202 or the CS150. Since you have a single input wetdry I would sway more toward a single output for ease of installation and less hoses in the way. Dont forget to get the aqua lifter pump and if you really want it even more quiet then buy or make a top out of acrylic..mine just sits up there and its helps some in sound and with less water evaporation.

[madugo]

Having looked at the CPR units, I like them and I would run one or two of them.
If I was you, I would get the 1.5" units, then reduce it down into the fitting on the wet/dry. What size wet/dry you running ? Home made ? Or brand name ?

Pictures helps !

i dont know what brand is it...but it is pretty big tho...i think that that is more than 25 gallon or so...its like 30 something inch long...i will try to put a pic if i can ..

[madugo]

I have the CPR CS202, which is probably the dual one you are speaking of...It works great and is VERY quiet once you mess around and move the hoses in the right spot. Keep in mind the flow rates are advertised with no sponge prefilter or screen in place. If you have small fish like tetras sized, they will fall into it if you dont use the screen...and even some very small fish can slip thru the holes in the screen.

I dont think you can go wrong with either the CS202 or the CS150. Since you have a single input wetdry I would sway more toward a single output for ease of installation and less hoses in the way. Dont forget to get the aqua lifter pump and if you really want it even more quiet then buy or make a top out of acrylic..mine just sits up there and its helps some in sound and with less water evaporation.

i am glad to hear that its quite..the tank is for my mbu puffer, its most likely gonna be one fish only...
and i will get the one with aqua lifter, it just looks much easier and trouble free...

[madugo]

madugo,

I'm assuming you have a mag 12 that pushes1200gph. Like Traci said, you don't have to match the pump rating to the overflow rating. You just have to make sure the overflow rating is higher than the pump rating.

This is the odd thing that happened to me. I got a mag 12 and a dual overflow with 1" bulkheads so I thought that would be fine. I have about 4'' headheight so the pump can not being doing 1200gph.

However, when I hooked everything up the pump was moving too much water for my overflow box. I had to buy a PVC ball value and install that between the return line to lower the flow.

So I actually think the standard flow rate from a mag 12 is either a little more than 1200gph or the standard flow rate from a overflow box with two 1'' bulkhead is lower than 1200gph. Either way the PVC ball value allowed me to lower my flow rate and find the balance that I wanted. You might want to look to getting one. They are like 3 bucks at any hardware store.

Good luck with your system man. Call me if you need any help.

i think i may run into that problem when i set it up...and my friend is gonna help me to set it up tho...he mentioned that ball value thing to me too..so if i run into that problem...i will do that than...and if i run into more problem, i will call u and ask u thai..thanks man...

[madugo]

You want the overflow box to be able to flow more than the pump you are using. The only problem you'd ever run into is if the pump was pumping water faster than it could flow through the overflow box back down to the sump.

Only the water in the tank that rises above the lip of the overflow box can flow down to the sump. If the pump is fast, then more water will flow over the lip, into the overflow box, and down to the sump. If the pump is slow, then less water will flow over the lip, into the overflow box, and down to the sump.

Fast pump --> slow overflow = too much water returning to the main tank and potential for overflowing the main tank.

Slow pump --> fast overflow = water from main tank must get over the lip of the overflow in order to flow to the sump, so only the water returned to the tank via the pump contributes to the water level going over the lip of the overflow box to flow to the sump.

So if the pump moves water faster than it can flow through the overflow, the water level in the main tank would rise until it overflowed the tank. This is why the overflow box should never have a lower flow rate than the pump.

Make sense? It's hard to put it into words.

i think you did really good explaining on them Tracy, thank you for the lesson, i think i basically have an idea now..and i think i will know which one i am getting too..will try to do a tank jouney later.

[myjohnson]

i think i may run into that problem when i set it up...and my friend is gonna help me to set it up tho...he mentioned that ball value thing to me too..so if i run into that problem...i will do that than...and if i run into more problem, i will call u and ask u thai..thanks man...

let me know how it goes. My girl's apartment is not to far from your place. If you need me to come over and help with installation I can do that.

[madugo]

let me know how it goes. My girl's apartment is not to far from your place. If you need me to come over and help with installation I can do that.

lol...thats so nice of you..
but i think my friend is gonna help me with it..so it should not be a big problem, but i will let you know if i run into something..
check your pm tho, i did send you a pm regarding something..