Overflow inlet pipe size and return size.

[thatone08]

Hello,

I just ordered a new sump and I am going to take this opportunity to fix some beginner mistakes.

Tank is corner over flow that originally had a 1 inch and 3/4 inch hole drilled. I drilled my own return, and used the 2 holes for inlets to the sump. Sump only had a 1 inch input so the 3/4 was the emergency and I just plumbed it leading into skimmer area loud enough to alert me the main o e was clogged.

New sump has two inch inlets. What are thoughts on swapping one of the bulk heads on sump to 3/4 and having that as my main, matching my return. Then using the 1 inch as the emergency.

Thought about moving the 3/4 to 1 inch most of the way, but feel like that would be very loud.

I know I can put a ball valve on to adjust but I feel like that would just be asking for a clog.

Any recommendation on maki g it work, as quiet as possible. Would be ok if full flow through emergency was loud.

 

[Bret]

How much flow do you need through your sump?
1" drain size is plenty for most setups, and a 3/4" secondary is also probably fine, since your main will be restricted (use a gate valve) to establish full siphon.
On the return side, you want to go as large as you can. 3/4" will place a huge restriction on your return pump. Unless you are shooting for very low flow, I would up that as much as you can. 1.25" is a good size for most returns (split into two smaller returns when entering the tank is fine. The idea is to reduce the head pressure from pipe friction and all the fittings for the majority of the run).
I made a post a while back about setting up and tuning a Herbie style overflow setup. I'll see if I can find it and re-post it here.

 

[VB313]

Kind of in a similar situation I’m going to post a build thread later this week

I changed my center over flow with a stock 1” and 3/4” bulkhead into a herbie drain 3/4 is a main drain with a gate valve close to sump 1” is now my emergency and run my return line up and over the thank glass

I had to use a large return pump with 1” pipe to compensate for head pressure since my sump is in the basement but I plan on using a gate valve to lower the flow to allow the 3/4 to handle appropriately

 

[thatone08]

How much flow do you need through your sump?
1" drain size is plenty for most setups, and a 3/4" secondary is also probably fine, since your main will be restricted (use a gate valve) to establish full siphon.
On the return side, you want to go as large as you can. 3/4" will place a huge restriction on your return pump. Unless you are shooting for very low flow, I would up that as much as you can. 1.25" is a good size for most returns (split into two smaller returns when entering the tank is fine. The idea is to reduce the head pressure from pipe friction and all the fittings for the majority of the run).
I made a post a while back about setting up and tuning a Herbie style overflow setup. I'll see if I can find it and re-post it here.

On my current sump I have the 1 inch drain with gate valve as my main, with 3/4 as the emergency and it’s worked fine. It’s a 30 gallon tank so I’m not sure if 3/4 is that much restriction on that size tank? Current way it’s setup I have a decent amount of flow through sump. But confused on what’s better more sump turnover or less. With less having more contact time for skimmer, and new sump will have a small refugium section that I’ll be trying chaeto for the first time.

 

[Bret]

On my current sump I have the 1 inch drain with gate valve as my main, with 3/4 as the emergency and it’s worked fine. It’s a 30 gallon tank so I’m not sure if 3/4 is that much restriction on that size tank? Current way it’s setup I have a decent amount of flow through sump. But confused on what’s better more sump turnover or less. With less having more contact time for skimmer, and new sump will have a small refugium section that I’ll be trying chaeto for the first time.

For a 30g tank your plumbing is appropriately sized. For flow through the sump I’d aim for between 150 and 300gph. Keep in mind that you will see significantly less flow than your pump is rated for, likely only ~1/3 of its max rated output