New tank design graphic ... Tell me what you think...

[Megalodon]

Originally Posted by mark

It should work if I'm understanding your last drawing plus making an assumption. Plus a Herbies as not drawing air are silent.

All three of you bulkheads are drilled to the same height, and within the tank you have a 90° pointing up (assumption). The heights in the tank of B and the one on the right (connected to E) are the same, with 1 being higher than the other two. On 1 and Z you have no valve and is the backup.

That is correct. The backup overflow is higher than the other two. The backup drain line also doesn't have a gate valve and it's completely unrestricted.

Originally Posted by mark

Something that might take some playing. I was doing some experimenting with a Herbie in a 33g running with no overflow box, just a standpipe coming up in the corner from a 1" bulkhead in bottom of the tank. Was just using a little pump so flow was 230gph. I adjusted the valve so the water stayed at a steady height and ended up I had 2 7/8" of water above the top of the standpipe. Where the playing comes in is adjusting the standpipe so the final water level is where you want it.

Yeah, it will definitely take some playing with the pipe heights. I will not glue anything in place until I achieve the perfect height. And since the tank will be acting as the overflow I'm assuming that if the power goes out I'll need a larger sump to take up the additional water.

Increasing the size of my refuge and sump are in the works now. I saw some unusual tanks at Big Al's that might work. The sump will then be 25 gallons and the refuge 20. If my CorelDraw trail doesn't expire I'll try and post an updated diagram.

[Megalodon]

OK, the sump I had in mind might be too tall to be able to take the protein skimmer in and out if I needed to.

Since my sump won't be able to handle the water from the tank in the event of a power outtage, how large should my external overflows be?

[Myka]

Originally Posted by Megalodon

That is correct. The backup overflow is higher than the other two. The backup drain line also doesn't have a gate valve and it's completely unrestricted.

In your drawing it looks like all your bulkheads are the same height. How are you going to get your backup overflow higher than the primary overflows without having to keep your entire tank water level much lower than the rim of the tank? You need to have quite a height difference between the backup drain and primary drain(s).

[Megalodon]

Originally Posted by Myka

In your drawing it looks like all your bulkheads are the same height. How are you going to get your backup overflow higher than the primary overflows without having to keep your entire tank water level much lower than the rim of the tank? You need to have quite a height difference between the backup drain and primary drain(s).

No, the backup overflow is higher. Regardless, I've decided to heed your advice, as the way I was going to do it would require a larger sump to take up access water in the event of a power outage.

Check out my next revision. Tell me if my overflow box sizes look OK in relation to the tank size.

[Megalodon]

OK, this will probably be my final revision...

I've added Herbie overflows and a larger refuge.

A - 3/4" overtop PVC return manifold
B - 1" bulkhead and strainer leading to external overflow box
C - 1" Herbie backup overflow drain
D - 1" Herbie drain and strainer
E - External glass overflow box
F - 1" Spaflex backup drain pipe (left)
G - 1" Spaflex drain pipe
H - 3/4" Spaflex return pipe
I - 1" Spalfex drain pipe (right)
J - 1" Spaflex backup drain pipe (right)
K - ½"gate valve teed off from return
L - ½" Spaflex refuge feed from return
M - 20-gallon glass refuge
N - refuge light
O - 1" drilled bulkhead/refuge overflow
P - 3/4" Spaflex refuge drain
Q - 3/4" Spalfex refuge backup drain
R - 20-gallon glass sump w/ large return area
S - Baffles more than 1" apart
T - Eheim 1262 return pump
U - AquaC EV-180 protein skimmer
V - Drain area with filter sock

* White pipes are dirty tank drain water

* Grey pipes are clean return water

* Pink pipes are backup only and won’t usually have water in them

[mark]

Not sure of any formula for the size of overflow box other than on RC's (here) where they mention linear weir length.

Picture is of Skimmin's set up. (clearer picture here). Those boxes were handling ~1000gph each.

[Myka]

Ya, I'm not sure on the overflow box size either. I haven't got that far in my plans.

I don't think you'll be able to regulate the flow well enough on your drains without putting a separate gate valve on each one. Now, I'm just wondering here, but is there a reason you aren't drilling your returns?

[Megalodon]

Originally Posted by Myka

Ya, I'm not sure on the overflow box size either. I haven't got that far in my plans.

I've decided to make them 17cm long, 20cm deep, and 10cm wide.

Originally Posted by Myka

I don't think you'll be able to regulate the flow well enough on your drains without putting a separate gate valve on each one. Now, I'm just wondering here, but is there a reason you aren't drilling your returns?

I'm going to do that now too. See my next diagram. (Yes, sorry, another one, LOL.)

I'm not drilling the returns because I'm not sure if the sump will be big enough to take up the access tank water during a power failure.