Pipe diameter vs flow rates (and more)

[CRAP! Another Hobby]

OK...totally scrapping the 55 g reef that we just spent hundreds of dollars on. "WHY?" you may ask...well ...because now we are going to use a 90 g for the reef and the 55 for the sump!

My question is this...OK, maybe a few questions...well...maybe more than a few questions

***NOTE*** Since it (the 90 g) is a Hagen tank...I am assuming that the bottom will be tempered (non-drillable) glass. I will need to make another "OVERFLOW PIPE" as I did for my discus tank.

Does it really matter if my pipe from the tank to the sump is 1", 1.5"...2"? (Any ideas what the flow rates are??)

How much Flow through the sump is "ideal?" (Not counting the slow flow fuge)

Pump recommendations?! Mag5/7/9???

SCWD...is it worth it?

More "sump" area than refuge...or the other way around??


Any and all advice is welcome

[fkshiu]

Diameter of your overflow pipe does matter. Obviously the larger the pipe the more it can flow. But you don't want to go too big as you'll run into air injestion issues (i.e. gurgling).

Here's a useful calculator for minimum drain size:
http://www.reefcentral.com/calc/drain.php

The size will also be dependent on the type of overflow you are using whether it be a Durso, Herbie or some other method.

There are a myriad of choices for return pump. The first choice you have to make is whether to go internal or external. I prefer external since the pump is easier to service and you don't get anywhere near as much heat transfer. I use an external Eheim 1260 which is is more expensive than Mags, but is much better quality, quieter, uses less electricity and transfers much less heat. One thing you should look for in a sump return pump is to make sure that it is "pressure rated" this means that it is designed to pump upwards against gravity. Pumps that are not pressure rated lose a lot of oomph the further upwards it has to push water.

Here is a useful head loss calculator that takes into account your own unique plumbing situation:
http://www.reefcentral.com/calc/hlc2.php

As far as flow through the sump goes, some people want an extremely powerful return pump providing most of their tank circulation. However, too powerful a return pump can result in more microbubbles, salt creep from the splashing and a noisier overflow. It can also decrease skimmer effectiveness as the water zips by before the skimmer can process it. I just want my return pump to get the water back into my display tank, so I aim for about 2-3 times total system turnover per hour.

I think SQWDs are great little inventions for smaller tanks but no so much for bigger ones because their switching rate is dependent on flow rate. So a bigger pump on a bigger tank will cause it to switch back and forth much more that you'd like it to. SQWDs have also developed a reputation for gumming up and stopping for some people and you can't take it apart to clean it. They also cut back on your pumps head pressure as well.

[Pan]

Don't hagen tanks only have tempered bottoms? You could drill the back...don't quote me on this but i think it is just the bottoms.

[fencer]

Get some sunglasses out and check to see if it is tempered

[Treebeard]

Thanks for posting the link to the head loss calculator. I ordered a new sump yesterday and have an 11 foot lift from the sump to the display. This will certainly help in finding the right pump for the job.

[CRAP! Another Hobby]

Originally Posted by fkshiu

Diameter of your overflow pipe does matter. Obviously the larger the pipe the more it can flow. But you don't want to go too big as you'll run into air injestion issues (i.e. gurgling).

Here's a useful calculator for minimum drain size:
http://www.reefcentral.com/calc/drain.php

The size will also be dependent on the type of overflow you are using whether it be a Durso, Herbie or some other method.

made an excellent overflow for my discus tank. I wrote a DIY article for a discus forum. You can read it HERE It is very quiet and is currently handling 400 gph without much gurgling

Originally Posted by fkshiu

There are a myriad of choices for return pump. The first choice you have to make is whether to go internal or external. I prefer external since the pump is easier to service and you don't get anywhere near as much heat transfer. I use an external Eheim 1260 which is is more expensive than Mags, but is much better quality, quieter, uses less electricity and transfers much less heat. One thing you should look for in a sump return pump is to make sure that it is "pressure rated" this means that it is designed to pump upwards against gravity. Pumps that are not pressure rated lose a lot of oomph the further upwards it has to push water.

Here is a useful head loss calculator that takes into account your own unique plumbing situation:
http://www.reefcentral.com/calc/hlc2.php

As far as flow through the sump goes, some people want an extremely powerful return pump providing most of their tank circulation. However, too powerful a return pump can result in more microbubbles, salt creep from the splashing and a noisier overflow. It can also decrease skimmer effectiveness as the water zips by before the skimmer can process it. I just want my return pump to get the water back into my display tank, so I aim for about 2-3 times total system turnover per hour.

All excellent info!!! I will keep it in mind when I get to pump shopping!

Originally Posted by fkshiu

I think SQWDs are great little inventions for smaller tanks but no so much for bigger ones because their switching rate is dependent on flow rate. So a bigger pump on a bigger tank will cause it to switch back and forth much more that you'd like it to. SQWDs have also developed a reputation for gumming up and stopping for some people and you can't take it apart to clean it. They also cut back on your pumps head pressure as well.

Maybe better used for a closed loop...something for us to think about. Thanks for the great info