help sizing bean animal overflow & pump

[Steveb]

I have a 8' 400 gallon acrylic tank that I am pulling the two internal overflows off of starting tomorrow and converting to coast 2 coast. The sump is another 90g or so. The skimmer is an older SWC 300a w/askoll 1500 rated from 300 - 500 gallons depending on bioload.

Using the hydraulics calculator for a submerged discharge tube that is 42" in height, I came up with 2205 gph, 3445 gph and 4961 gph for 1", 1.25" and 1.5" plumbing respectively.

I have several questions...

What is the recommended circulation turnover rate for correct filtration? 4x 10x ?? Will be a mixed reef + fish

Is that what is used to determine which bulkhead size? Should I entertain 2"?

What should the height and depth of the coast 2 coast weir be (just large enough to hold selected plumbbing size? Will have NO TEETH...

The length of the weir will be 80" - 84"..

I have a new reeflo dart and a couple of darts that have been rebuilt (for backups) but would consider a larger pump if that is what is needed.

I want to make sure the BA overflow starts with no issues so all feedback based on experience is appreciated. :thumbsup:

 

[uncleof6]

I have a 8' 400 gallon acrylic tank that I am pulling the two internal overflows off of starting tomorrow and converting to coast 2 coast. The sump is another 90g or so. The skimmer is an older SWC 300a w/askoll 1500 rated from 300 - 500 gallons depending on bioload.

Without going throught he whole iteration on skimmer sizing, that skimmer is about 3x too small for the system (400 gallon) for sizing based on gallons volume, it is usually necessary to multiply the gallons by three...this is becasue skimmer makers have no standards, or formulas, (they don't exist) for which to size a skimmer. It is guess work, and there is enough anecdotal information to assume they are always going to be too small, if based on gallon size.

By flow through the skimmer (THROUGH THE SKIMMER, not past it) generally 2x - 3x the system volume per hour works out.

Using the hydraulics calculator for a submerged discharge tube that is 42" in height, I came up with 2205 gph, 3445 gph and 4961 gph for 1", 1.25" and 1.5" plumbing respectively.

I have several questions...

What is the recommended circulation turnover rate for correct filtration? 4x 10x ?? Will be a mixed reef + fish

4 grand...

Is that what is used to determine which bulkhead size? Should I entertain 2"?

1.5" bulkhead with 2" pipe...

What should the height and depth of the coast 2 coast weir be (just large enough to hold selected plumbbing size? Will have NO TEETH...

The length of the weir will be 80" - 84"..

Don't know. Takes a measuring tape, plumbing parts, and a little math to figure that out.

Weir: 1" - 1.5" below the top of the tank
Bottom of overflow (height): ~1" below the bottom of the downturned elbows.

I have a new reeflo dart and a couple of darts that have been rebuilt (for backups) but would consider a larger pump if that is what is needed.

I want to make sure the BA overflow starts with no issues so all feedback based on experience is appreciated. :thumbsup:

Guess what? Sounds like a barracuda/hammerhead hybrid to me...hammerhead front end.

I run bacarudas on 300+ gallon tanks....the dart is a little limp for that size, (cutting it too close) but will get the job done....400 gallon? Nope.