Some help on a closed loop...

amnesiac · Nov 16, 2019

Hey all. I'm getting in a new frag tank and was seriously considering a closed loop for flow. Initially, I was just going to throw in a couple of gyres and some Tunzes and call it a day, but then thought how much easier a closed loop system would be, as far as maintenance goes. Throwing the lever on a couple of valves and cleaning one massive pump beats having to pull out 4 powerheads any day. Plus I already have 4 or five return pumps on the shelf collecting dust. The tank will be a 6'x 3'x 1' (approximately 130 gallons) with my plan being to drill 2 inputs on the bottom near one side and put 2 or 4 outlets on the opposite side wall. The pump I'm looking to use is a Panworld 1750GPH. So here are my questions:

1. What size should my drain and output bulkheads be?
2. Is a 1750GPH pump for a tank this size adequate/inadequate/overkill?
3. This is going to have mostly SPS. Knowing that is the steady flow of a closed system not utilizing any sort of wave making device (think Oceans Motions) detrimental to the health or growth of my SPS?

Since I already have just about everything I'd need to put a closed loop system in I'd save myself well over 500 simoleons if I could go this way so I figured it was worth asking a few questions. Appreciate any help you can give, guys. -A

mfinn · Nov 16, 2019

Alot of things to consider.

1. The drain is one thing you shouldn't skimp on. I would go minimum 1-1/2" bulkhead. Even if the suction side of your planned pump is smaller, you may want to change pumps and you never know what the suction side of the future pump will be. You can always use reducer bushings to match your current pump.
2. I would figure at least 4 returns so it may be small, BUT it's 1750 gph you will have without a cord in the water.
Plus you could look into flow actuators ( whatever they are called)
3. I would figure on adding something that will give you a random flow.
I know you didn't want to deal with powerheads, but you can use the CL to get water moving around and a powerhead to break up the flow into random flow.

ca1ore · Nov 16, 2019

PW200 will be OK, particularly if you already own one. Something like a vectra is much better though because you can dynamically vary flow. Thus not need to run an oceans motions type device. Agree to go 1 1/2” on the suction side just in case. 1” will suffice on the outputs. If you do use the PW200 than get some VCA nozzles to help randomize flow.

amnesiac · Nov 17, 2019

Thanks for the reply guys. I feel like a complete idiot even posting. After digging around my supply closet I found a brand spankin' new Reef Octopus Varios 8. With this I can vary the flow plus it's pumping out about a thousand GPH more than the Blueline. Still, I appreciate the help on the bulkhead sizing. I'll go with 1 1/2" on the drain and 4X 1" on the returns. I guess the Blueline will sit in the back until I need another water station lol. Thanks again guys!!!

William Norman · Nov 17, 2019

amnesiac said:
Thanks for the reply guys. I feel like a complete idiot even posting. After digging around my supply closet I found a brand spankin' new Reef Octopus Varios 8. With this I can vary the flow plus it's pumping out about a thousand GPH more than the Blueline. Still, I appreciate the help on the bulkhead sizing. I'll go with 1 1/2" on the drain and 4X 1" on the returns. I guess the Blueline will sit in the back until I need another water station lol. Thanks again guys!!!

Amnesiac - can I come over an explore in your closet? Sounds like you have a lot of goodies hidden in there.

amnesiac · Nov 17, 2019

William Norman said:
Amnesiac - can I come over an explore in your closet? Sounds like you have a lot of goodies hidden in their.

Bruh, that was the tip of the iceberg. Also, found a beast of a Waveline DC pump and a couple of Tunze powerheads, as well as 4 expired Hanna alk reagents. All unopened!!! I'm starting to remember a BRS sale that I couldn't pass up. Explains a lot really.

ca1ore · Nov 17, 2019

Living up to your username lol. Though I recently had occasion to swap out my Blu-ray player (yes, I still buy discs). Opened up the cabinet, couldn’t remember what all the wires were .... closed it again.

amnesiac · Nov 17, 2019

ca1ore said:
Opened up the cabinet, couldn’t remember what all the wires were .... closed it again.

;Hilarious;Hilarious;Hilarious

JumboShrimp · Nov 17, 2019

Any other "spankin' new" stuff I can 'dig around in your supply closet' and find?.. I'm available to come over... LOL

Best wishes on your project.

amnesiac · Nov 17, 2019

JumboShrimp said:
Any other "spankin' new" stuff I can 'dig around in your supply closet' and find?.. I'm available to come over... LOL
Best wishes on your project.

LOL. Thanks, boss!

amnesiac · Dec 28, 2019

OK guys, need a bit more help. So I sold off some of those pumps and decided to keep 2 Waveline DC12000's to use as my closed loop engine. I really didn't want to do it, but for piece of mind I'm going to add 2-4 AC Tunze NanoStreams. The Tunze's will be placed opposite the return for the closed loop (space won't allow me to have returns for the closed loop on both sides. The Tunze's will be at the bottom of the tank to sort of sweep up any debris and keep it suspended. Only thing I'm unsure about is what to put on the bulkheads for the CL returns. I was going to have two 1" bulkheads per pump and fashion some flare nozzles out of 1" PVC. However, I started thinking that I'd like the options provided by throwing a Loc-Line NPT connector on there. Thing is 3/4" is the biggest they come in and at 2x 3/4" per 3170GPH pump I worry if I'd be bottlenecking the flow for the CLs. I've included a pic (in my best Doc Brown voice "Please excuse the crudity of this model"). Please have a look and lemme know if you think and if anyone can tell me whether or not 2x3/4" Loc-Lines can handle a single 3170GPH pump I would appreciate it immensely. -A