Wow nice setup! I want to move solids like that. As far as the overflows I have 1 on each side, should they both be set at water level? Or one below? Both below? I'm confused on that part
Overflow help for 450 gallons
- Thread starter Torchia32
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That is a good question.mine skim the surface only but I have seen some that have mid and bottom inlets that look intriguing. My weirs hold about fifteen gallons and each have a small school of zebra danios in them that eat food that gets sucked in there. I also dropped an internal filter full of purigen in each to keep the water crystal clear.
I would strongly advise you to go with 2 of the 2 inch drains in each overflow--for a total of 4 drains and 2 returns. Reason why is this--you may well decide to do a Herbie overflow because it's quiet, and it drains LOTS of water at full siphon. If you don't want to do a Herbie, no problem, plug one of the drains in each overflow. But, if you decided later to do a Herbie and didn't already have the holes drilled and the overflow boxes sized for 3 holes, you'd have to tear the tank down, drill the extra hole, and re-do the overflow. It's a pain, and it would take some time to do it right and not mess up.
Let the tank builder do all that. They do it alot more than you or I do. They can do it alot easier in a shop with a crane, before the put overflows in place anyway. Easier for them to do it than you. Won't cost you anymore.
Also, you may not want to do vertical overflows. If it was me, I'd do the coast-to-coast overflow across the top of the tank, and Beanimal type drains.
I think you should consider running 2 2900 Laguna's. One seems kinda light to me.
You might consider running 1.5 inch drains if you go with 4 drains and a Herbie. I have the 2 inch drains, and they are overkill. I'd say 1.5 inch drains would have done me just fine. I got 2 inch drains because I just HAD to be SURE I could drain 5,000 - 6,000 Gallons per hour. You should decide, first, what you want to flow, or possibly later COULD want to flow. Then you size drains to that flow rate. The guy who invented Beanimal type drain system posted the drain rate of PVC pipe here.......http://www.reefcentral.com/forums/showthread.php?t=1814606
Let the tank builder do all that. They do it alot more than you or I do. They can do it alot easier in a shop with a crane, before the put overflows in place anyway. Easier for them to do it than you. Won't cost you anymore.
Also, you may not want to do vertical overflows. If it was me, I'd do the coast-to-coast overflow across the top of the tank, and Beanimal type drains.
I think you should consider running 2 2900 Laguna's. One seems kinda light to me.
You might consider running 1.5 inch drains if you go with 4 drains and a Herbie. I have the 2 inch drains, and they are overkill. I'd say 1.5 inch drains would have done me just fine. I got 2 inch drains because I just HAD to be SURE I could drain 5,000 - 6,000 Gallons per hour. You should decide, first, what you want to flow, or possibly later COULD want to flow. Then you size drains to that flow rate. The guy who invented Beanimal type drain system posted the drain rate of PVC pipe here.......http://www.reefcentral.com/forums/showthread.php?t=1814606
That is really good advice David, if I had thought things through I would have had the extra hole drilled at the time of construction. Even if I never use it for a drain I could have run the power cords up through it. I think it's a good idea to have each overflow be able to handle the full flow rate individually as well in case one side fails for some reason.
As for whether the drain should be at water level, one above/one below, all that......let's think about one overflow for the whole tank just to keep this simple to explain. Originally, you'd have a single drain, water would fall in it and exit in the sump. That was pretty loud, so they invented the Durso standpipe. That was kinda hard to adjust, not quite quiet enough, so they came up with the Herbie drain.
Herbie would have drain about 6 inches below the water level with a very finely adjustable ball valve or gate valve. The second drain would be an emergency, in case the ball valve got slimed up a little and started draining a little slower. After a while, with no backup drain, you'd eventually flood the house. The emergency drain is at or above the water level, depending how quick the main siphon is draining, and it drains the overflow box if the main siphon drain falls behind the input rate of the pump. When that starts, you open up your ball valve a little to get the main siphon drain to match the pump output rate, so the emergency drain is dry.
Then, they came up with the Beanimal. It's a Herbie with 3 drains. It's an improvement over the Herbie in that it is truly self tuning, automatic. I have to adjust the valve on my Herbie setup every 2-3 months for one reason or another. You never have to adjust a BeanAnimal.
I have a Herbie on my tank. I wish I would have spent more time reading about the BeanAnimal and coast-to-coast overflow. I thnk it's the way to go if you're having a tank built.
Herbie would have drain about 6 inches below the water level with a very finely adjustable ball valve or gate valve. The second drain would be an emergency, in case the ball valve got slimed up a little and started draining a little slower. After a while, with no backup drain, you'd eventually flood the house. The emergency drain is at or above the water level, depending how quick the main siphon is draining, and it drains the overflow box if the main siphon drain falls behind the input rate of the pump. When that starts, you open up your ball valve a little to get the main siphon drain to match the pump output rate, so the emergency drain is dry.
Then, they came up with the Beanimal. It's a Herbie with 3 drains. It's an improvement over the Herbie in that it is truly self tuning, automatic. I have to adjust the valve on my Herbie setup every 2-3 months for one reason or another. You never have to adjust a BeanAnimal.
I have a Herbie on my tank. I wish I would have spent more time reading about the BeanAnimal and coast-to-coast overflow. I thnk it's the way to go if you're having a tank built.
Wow you guys are giving absolutely awesome advise. I have decided to just have 2 overflows and 2 returns 1 on each side of tank. The setup is in my basement and is an extra tank that I'm not too worried about so noise isn't an issue. So if I have 1 return and one drain in each of the 2 back corners what height should I set each of the standpipes at in relevance to the water level?
IF you can drain the pump output with just one drain, then you would cut one standpipe so that it is about an inch or two below the bottom of the teeth in the weir. The idea is to have water come into the overflow box through the teeth on the weir, and fall an inch maybe. That creates some turbulence before it goes in the standpipe, so air gets in the water, surface film can't build up, etc. That COULD be a problem with a ball valve on a drain and smooth flow down into the sump.
If you cut the standpipe a touch higher than the teeth on the weir, then you'll notice that the surface of the tank, and the overflow box, stays very calm and film can develop, gets scummy, etc. Kinda have to see it.
Now if 1 drain can't handle the pump output alone, just cut the standpipes the same height because the water level will be the level set by the highest standpipe anyway.
When you're setting this all up, there's some trial and error--you might cut the standpipe a few times til you get it just right. It's very handy to have a ball valve underneath the tank so you can close it, pull the stanpipe outta the bulkhead, without draining the overflow box. Not a necessity, but kinda handy.
If you cut the standpipe a touch higher than the teeth on the weir, then you'll notice that the surface of the tank, and the overflow box, stays very calm and film can develop, gets scummy, etc. Kinda have to see it.
Now if 1 drain can't handle the pump output alone, just cut the standpipes the same height because the water level will be the level set by the highest standpipe anyway.
When you're setting this all up, there's some trial and error--you might cut the standpipe a few times til you get it just right. It's very handy to have a ball valve underneath the tank so you can close it, pull the stanpipe outta the bulkhead, without draining the overflow box. Not a necessity, but kinda handy.
Thanks again for all that great info Cajun. I'm actually not going to have overflow boxes at all. The tank is going to be bare so I'm not concerned with debris entering. And the fish I am keeping are nearly both 20" in length so I'm not worried about them getting sucked in either. So if I'm understand you correctly you are saying to set one pipe at water level and have another pipe slightly below water level?
If you don't do a silent drain, with full siphon drain, you'll have significantly lower drain rate in the pipe than the rates shown in the link I posted earlier. You'll have to research what expected flow rate is under "turbulent flow conditions". I know that a pair of 2 inch drains can handle my 2 2400 Laguna's. So if my gate valve ever just clogged up totally, I'd still be OK. It'd be loud, but it wouldn't flood.
Problem I see is this. Suppose you find that a single Laguna 2900 isn't enough flow. If you want to add second one, (which is what I'd do to start), you might not have enough drain capacity to keep up.
Problem I see is this. Suppose you find that a single Laguna 2900 isn't enough flow. If you want to add second one, (which is what I'd do to start), you might not have enough drain capacity to keep up.
