Plumbing pipe size question

[ryudo80]

I'm about to custom order an acrylic reef tank with sump. I've never had a sump before so I want to get it right when ordering. Here are the specs of the tank I plan to order:

Tank: 72x24x22(tall) acyrlic, with 3/4 inch front, back and sides with 1/2 inch top and bottom. I think the actual water volumn is around 145 gallons.
Overflow: External right corner for easier maintenance reach. Dimension of overflow box is 12x6x12 that the builder uses. I don't know if this is a good enough size.
Return: 1 return on left corner

I want to do a bean animal for the overflow with 3 pipes. What size pipe size should I be using? is it possibel to use 1 inch bulk heads inside the overflow box to save space and transition to 1.5 inch drain pipe under the overflow box to reduce noise and improve drain? or should I use 1 inch drain drain all the way through? Or perhaps 1.5 inch drain and 1.5 inch bulk heads?

Also, for the single return, what pipe size should I be using? I think it's either 3/4 inch or 1 inch but I'm not really sure. I plan to use a gyre on the same side to push surface water to the overflow on the far end.

 

[DCR]

I would use two 1" returns on a tank that size. They should each easily carry 500 gpm with a properly sized pump. The 3/4" returns are very restrictive IMO and not suited for a tank that size. I think you can use a 1" for the drains if you are using a 3-drain bean although it may restrict your overall return flow somewhat. 1-1/2" would probably be preferred for the overflows. I would match the pipe to the bulkhead size.

 

[ryudo80]

Thank you for the suggestions. I thought about 2 returns, 1 in the end and 1 in the middle but decided against the middle one as I want to avoid any maintenance in the middle back of the tank that will be hard to reach. Perhaps 2 returns on the same corner but spaced out by 12 inches or so.

 

[mfinn]

On my 240 I use the 3 drain system ( bean animal style with external overflow box) and use 1" drains all the way. I also have a single 1" return, which actually goes to 3/4" loc-line on the inside of the tank with a 3/4" Y and a pair of 1/2" fan nozzles.
I use a Red Dragon 3 100 watt as the return running at 46% for my return.

 

[jsmkmavity]

1" pipe will flow 50% more than 3/4". You can always turn it down but if your pipe is too small its very hard to increase flow.

 

[MasterClassReefs]

I am plumbing my system with 1.5" pvc all the way through. 1.5" returns in tank as well. 2" for UV manifold with a 1.5" bypass. My pumps have a 1.25" connection for returns, the increase in size for the pipes will reduce head pressure on the pumps. Smaller diameter pipes have a higher surface-area-to-volume ratio, causing higher frictional resistance.

 

[MasterClassReefs]

Thank you for the suggestions. I thought about 2 returns, 1 in the end and 1 in the middle but decided against the middle one as I want to avoid any maintenance in the middle back of the tank that will be hard to reach. Perhaps 2 returns on the same corner but spaced out by 12 inches or so.

Two returns and two return pumps would be a great idea for redundancy. If one dies your tank can continue running while you repair/replace.

 

[ryudo80]

On my 240 I use the 3 drain system ( bean animal style with external overflow box) and use 1" drains all the way. I also have a single 1" return, which actually goes to 3/4" loc-line on the inside of the tank with a 3/4" Y and a pair of 1/2" fan nozzles.
I use a Red Dragon 3 100 watt as the return running at 46% for my return.

I think for a 12 inch long overflox box, the 1 inch drain is probably the right option as I think the bulk head drilled will be close to 2.5 inch each. My concern reading about 1 inch drain is potential clogs. I assume you have not experienced any such log issue?

If I go with 1.5 drains, I think I will need to ask the builder for a longer overflow box, perhaps 16 or 18 inches.

 

[ryudo80]

I think I will go with 2 return lines, 1 inch each. I don't plan to have a ton of flow through my system because I mostly have LPS and soft corals in my current tank that I will move into the new system. I assume not using the full capacity of the 1 inch return lines won't produce too much noise. My current AIO system is basicallly silent so I hope to recreate that environment.

 

[mfinn]

I think for a 12 inch long overflox box, the 1 inch drain is probably the right option as I think the bulk head drilled will be close to 2.5 inch each. My concern reading about 1 inch drain is potential clogs. I assume you have not experienced any such log issue?

If I go with 1.5 drains, I think I will need to ask the builder for a longer overflow box, perhaps 16 or 18 inches.

Never had a clog ever.

 

[DCR]

I think for a 12 inch long overflox box, the 1 inch drain is probably the right option as I think the bulk head drilled will be close to 2.5 inch each. My concern reading about 1 inch drain is potential clogs. I assume you have not experienced any such log issue?

If I go with 1.5 drains, I think I will need to ask the builder for a longer overflow box, perhaps 16 or 18 inches.

If you are only going with a 12" or even a 16-18" overflow box, the 1" drains will be sufficient. The overflow box weirs will limit flow before the drains. I put a strainer over my main siphon to keep any fish that gets into the overflow from being washed down and it happens frequently with wrasses. The strainer needs to be cleaned periodically. The overflow and emergency are open ended and never clog.

 

[ryudo80]

I just looked at the Innovative Marine 200 Ext and it uses 3 1-inch drains. So 1 inch drain line is probably enough. That should also reduces water and plumbing weight dragging on the external overflow box.

 

[DCR]

FWIW - you could also get by with only a single 1" return if you are only going with a 12" overflow box. You will probably only be achieving about 3X per hour turnover rate with that system which I tend to think is fine for most tanks

 

[MasterClassReefs]

I think for a 12 inch long overflox box, the 1 inch drain is probably the right option as I think the bulk head drilled will be close to 2.5 inch each. My concern reading about 1 inch drain is potential clogs. I assume you have not experienced any such log issue?

If I go with 1.5 drains, I think I will need to ask the builder for a longer overflow box, perhaps 16 or 18 inches.

If you are only going with a 12" or even a 16-18" overflow box, the 1" drains will be sufficient. The overflow box weirs will limit flow before the drains. I put a strainer over my main siphon to keep any fish that gets into the overflow from being washed down and it happens frequently with wrasses. The strainer needs to be cleaned periodically. The overflow and emergency are open ended and never clog.

How large are your weir gaps for your overflow? I have never had any fish aside from fry end up in an overflow unless they jumped in over the top.

 

[MasterClassReefs]

I just looked at the Innovative Marine 200 Ext and it uses 3 1-inch drains. So 1 inch drain line is probably enough. That should also reduces water and plumbing weight dragging on the external overflow box.

Use pipe clamps and straps to avoid/eliminate this unnecessary stress on the box/bulkheads.

 

[DCR]

How large are your weir gaps for your overflow? I have never had any fish aside from fry end up in an overflow unless they jumped in over the top.

They are not going through the gaps. These are typically 2-3" flasher and fairy wrasses that are very prone to jumping and go over the top of the weir.

 

[MasterClassReefs]

How large are your weir gaps for your overflow? I have never had any fish aside from fry end up in an overflow unless they jumped in over the top.

They are not going through the gaps. These are typically 2-3" flasher and fairy wrasses that are very prone to jumping and go over the top of the weir.

Gotcha. You need mesh!

 

[Chuck_e]

Never had a clog ever.

I have. 1" drain got plugged by 3 worms that found their way into the weir and then down the line. I was seconds away from disaster, just happened to go into the room where the tank is and saw it starting to overflow. Panic shutdown of the return pump limited the loss to a couple of gallons. Can't do anything about the size of the drain, but I've added an optical sensor in the overflow chamber that will shut off the return pump if the level ever gets high.

 

[mfinn]

I have. 1" drain got plugged by 3 worms that found their way into the weir and then down the line. I was seconds away from disaster, just happened to go into the room where the tank is and saw it starting to overflow. Panic shutdown of the return pump limited the loss to a couple of gallons. Can't do anything about the size of the drain, but I've added an optical sensor in the overflow chamber that will shut off the return pump if the level ever gets high.

The OP was asking about drain size on a bean animal style ( 3 pipes) overflow and I mentioned I use 1" on mine, which is also a 3 drain system.
If we were talking about a single drain with no emergency drain, I would probably say at least 1-1/2".