Anyone still running a closed loop?

[Gregg @ ADP]

I like CLs for big (especially tall) tanks, mainly because it’s a lot easier to get flow along the bottom w/o blowing sand all over.

Good water flow along the bottom pushing up toward the top, and then let gyres/MP60s etc handle the flow and movement in the top 2/3

 

[MaddyP]

I'm planning a closed loop on a much smaller tank. CL are still relevant, though maybe not the most efficient. But, to achieve certain goals a CL fits the bill perfectly.

Mr Aqua 12g

 

[tigé21v]

I'm planning a closed loop on a much smaller tank. CL are still relevant, though maybe not the most efficient. But, to achieve certain goals a CL fits the bill perfectly.

Mr Aqua 12g

What in the world is going on under there??!

 

[Fin]

I ran a closed loop on my 140 for 12 years. A ReeFlo Dart with an OceansMotions 4 way valve. It had a 1½" intake (with the LifeGuard low profile screen) and four 1" returns - two on the bottom front corners and two at the upper front corners (with two of OceansMotions 1" OmniFlex nozzles). I only drilled 1 hole in the tank, for the 1½" intake. The two on the bottom front corners were fed by black PVC running down the back wall and under the sandbed. The two upper front returns ran inside the canopy to the front corners. The two bottom returns were buried in the sandbed and covered with rock rubble that was hot glued to the 45° PVC fittings. They were eventually covered with GSP and other corals.

The intake screen used originally was fairly large and I eventually went to the low profile screen from LifeGuard.
This shows the intake, all four returns and the black PVC that ran down the back wall, which was virtually invisible
in the tank. If you are wondering if the bottom returns blew sand all over the tank, they did not.

Rock rubble hot glued to the fitting. The hot glue held up well for the entire time the system was together.

The 4 way and plumbing running over the top of the tank.

This is the way the front returns were run along the inside of the canopy.

The bottom returns were well hidden by growth over the years. The intake was hidden by the large arch in the center of the
scape. I did add an MP-40 on the back wall and that is what is visible in the picture. The only visible part of the system were
the two upper front nozzles.

 

[MaddyP]

What in the world is going on under there??!

A closed loop!

I’ve decided to do a complete closed loop as I wanted the returns and drains on the bottom pane of the tank. If I were to do a sump with the bulkheads where they are the tank would drain if the pumps were to fail. All the quick connects are ports for the algae reactor, calcium reactor, media reactor, and Peltier heater/cooler. There also an additional port for water change and dosing lines.

I’ll be starting a build thread next week, everything is modeled in 3D.

 

[lapin]

I ran a CL for 3 years on my old tank. Worked great. Reef Flo dart and 2 Sea Swirls for returns. I read too much..... and decided that at that time, Oceans Motion had some reliabilty issues. Long intake strainers worked best for keeping critters out of the pump. Let me add Im not a fan of holes drilled in the bottom of a tank but that tank already had holes in the bottom.

 

[tigé21v]

The top rack of tees......
Are those all for probes??

 

[MaddyP]

The top rack of tees......
Are those all for probes??

Yes! PH, ORP, conductivity, temp, and dissolved oxygen.

 

[Shooter6]

I have a 180g now, i run 2 gyres on it and also 4 of the random flow nozzles on the returns from the refugeum. Im in the planning stage of going up to a 500+gallon display sometime in 2019. I just purchased a jebao dcq 1000 pump which will be plumbed to run a closed loop for currents. This pump has a wave setting. I tested it and its basically just a set pulse of on off. The intensity can be adjusted just like the speed when its running at the normal setting. I will use a bunch of the random flow nozzles plumbe to this pump, hidden in the rockwork to have completely random flow. This will be set to run a couple times a day for 3-4 hours each time. This should simulate the currents during the changes of high tide and low tide.

 

[jda]

Yes! PH, ORP, conductivity, temp, and dissolved oxygen.

The three probes in the middle will get stagnant and not get much water. The five outlet-thingys between the pumps on the bottom will be the same way. The water will rush from the in-tank drains directly to the input for the pumps.

 

[MaddyP]

The three probes in the middle will get stagnant and not get much water. The five outlet-thingys between the pumps on the bottom will be the same way. The water will rush from the in-tank drains directly to the input for the pumps.

The water through the middle section would indeed be low, but not anywhere near stagnant. Since the pumps will be ramping up and down opposite the other, water will pull from both drains to the pump running the higher flow. This should create a slight flow across the probes.