Help setting up overflow and return in new tank

[etherX]

I am setting up my first tank. I have a 60 gallon cube (24" x 24" x 24") and a 15 gallon sump. I bought an overflow box from modular marine for a smaller tank I thought I was going to set up and got a 600gph overflow box with 3 x 1/2" drains and one 1/2" return. Since I got the larger tank I know I need more capacity. I'm planning on 7.5x turnover through the sump, so 450gph. I'm going to start out with fish/softies, but want to add lps and sps eventually.

For returns, I was thinking either add another 1/2" return or return and get two 3/4" returns. The reason for multiple returns is so that I can eventually run 2 return pumps for redundancy. I'm inclined to stick with the smaller returns since with 2 it should be more than enough and I'm concerned about drilling (see more below). Thoughts?

For the overflow, I can either upgrade to a 1200gph box with three 3/4" bulkheads (for beananimal setup) or a 1600 gph box with three 1" bulkheads (also BA setup). If I do that, Due to required hole placement, I'll be pushing the "don't drill closer than the diameter of the hole to an edge or another hole" rule. I've been trying to figure out the flow rates for the 3/4" drains on full siphon, and it appears that they are in excess of 700gph, which would be more than enough, but since this is my first tank I thought I'd ask for help.

THANK YOU!

 

[etherX]

thoughts? help please!

 

[jacksonpt]

If you have a box that can flow 600gph, and you are targeting 450gph, why do you need a new box? Regardless, both of the larger boxes will be sufficiently overkill, so go with which ever one you feel more comfortable with. Do both boxes push the limits on space between/around holes?

I'm curious how you'll make 2 sumps work and what degree of redundancy that gains you that you wouldn't have from a properly designed single sump. But as for returns - are you planning over the top for returns (less drilling), or are you drilling them? Over the top gets you a lot of flexibility on number of outlets, placement, and ability to change over time. I'm not sure what the advantages are to drilling a return.

 

[etherX]

If you have a box that can flow 600gph, and you are targeting 450gph, why do you need a new box? Regardless, both of the larger boxes will be sufficiently overkill, so go with which ever one you feel more comfortable with. Do both boxes push the limits on space between/around holes?

I'm curious how you'll make 2 sumps work and what degree of redundancy that gains you that you wouldn't have from a properly designed single sump. But as for returns - are you planning over the top for returns (less drilling), or are you drilling them? Over the top gets you a lot of flexibility on number of outlets, placement, and ability to change over time. I'm not sure what the advantages are to drilling a return.

Thanks for the response. Apparently my original post is poorly worded. I'm not planning on 2 sumps, just (potentially eventually) 2 return pumps for redundancy in case one goes out. I'm planning to drill the returns, which is why I'm pushing the drilling limits. I'm doing that for a cleaner look.

Regarding return boxes, it's not the box capacity I'm concerned about, it's the drain capacity. I can get a 1200gph box with 3/4" drains (3, for bean animal setup), to get 1" drains I have to go with a larger box, which I'd rather not do unless I have to.

thanks again.

 

[jacksonpt]

OK, but why do you need the larger drain capacity? a 1/2" pipe at full siphon will flow way more than enough water for you, at least based on what you've proposed.

 

[etherX]

OK, but why do you need the larger drain capacity? a 1/2" pipe at full siphon will flow way more than enough water for you, at least based on what you've proposed.

This is exactly what I was wondering. Will the 3/4" at full siphon flow at least 600 gph (to be safe, I really am only planning on 450gph). To be clear, you think the 3/4" pipe is plenty? That would be great.

 

[jacksonpt]

Yes. I don't remember the numbers because I haven't cared about this in a long time, but at full siphon, I think a 3/4" line flows something like 1500gph (assuming you sump is under your tank... height of drop matters), and a 1/2" line flows 1000. Wait for someone else to chime in to be sure... but the 1/2 line is almost certainly enough, the 3/4" line absolutely is.

 

[cedwards04]

I have a 3/4" herbie style drain on my 40 breeder. I haven't measured to be sure, but I'm at roughly 350-400gph turnover after head pressure, and my valve is closed a good bit. 3/4" will for sure flow more than you need.

I would think the 1/2" will be enough honestly.