Closed loops: fish vaccuum?

[Hal]

How do you prevent your closed loop input from being a big fish vaccuum? Do you put a cage around it?

Is it more helpful to send the closed loop output through a sea-swirl or wavy-seas type device? Why not do this and not drill a second hole?

 

[bhdmc]

You can purchase a bulkhead strainer depending on the bulkhead size. They go for around $2.00 for 1/2" to $9.00 for 2". Or you can purchase eggcrate from you local Homepot/Lowes and contruct a cage around the bulkhead. I would use plastic tie-strap to hold the cage together. Homepot/Lowes also sell tie-strap. Attaching the cage to intake may create a problem depending on the location of the intake.

 

[BORNTOFLY]

http://www.melevsreef.com/closedloop.html

You will see on his that he use a long piece of PVC with holes drilled in it to prevent the fish blender.

both the SS and WS create random flow patterns the setup on the above page switches back and forth from each output pipe which also cause random flow.

Drilling is completely up to you. If your glass in not tempered drilling provides a cleaner look. I think most people would say aesthetics is the only reason to drill, I may be wrong we will just have to see.

 

[cward]

Although the strainer keeps things from getting sucked into the pump, animals still get stuck to the intake. I've had one chromis, and about 100 snails die from it.
I did add an elbow to keep the strainer away from the tank wall which helped a bit, but snails still have the urge to clean it.

 

[seaduck]

drill many holes in pvc with end cap then put a cylinder shaped sponge with a hole thru the center over the pvc...works great and the sponge acts as a pre-filter.

 

[MCary]

I tee'd my input to reduce suction. Of course I needed two holes. I then covered the bulkheads with bulhead strainers.

 

[LobsterOfJustice]

Find the size hole you will think you need. Now drill two holes in your tank that size, put strainers on them, and join the two intakes before the pump. You can also put a tee on the pulkhead on the inside of the tank, and put strainers on both ends of the tee. If you use both of these methods the suction is only 1/4 of what it was, plus you will probably get more overall flow, and you have "failsafes" incase anything gets clogged.

I would send the output through a seaswirl or wavysea, but to increase wavemaking... it wont help the suction at all.

 

[jwheeler]

I had an anenome decide to move right next to my closed loop intake thats built just like Melev's site shows. It sucked up his tentacles, then shot them out on both sides of the tank, and injured some of my other corals, like my open brain, but they all healed.

 

[chip721]

This is my CL intake screen. My anemone is no where near, yet even the small fish are strong enough not to get vacuumed. But my CL pump pushes water more than it pulls it. So the flow at the intake is basically a "moderately forceful" gravity fed siphon. It's enough to keep the pump happy, but not at all a fish sucking vacuum. HTH.

 

[Slickdonkey]

I had a local dude build me this closed-loop strainer. It works great -- nice even suction and no more sucking air (whirlpools) from the surface.

I have two 1.5" intakes for my closed-loop and used to have the strainers. This used to catch snails. This works much better.

 

[Hal]

<a href=showthread.php?s=&postid=8111909#post8111909 target=_blank>Originally posted</a> by Slickdonkey
I had a local dude build me this closed-loop strainer. It works great -- nice even suction and no more sucking air (whirlpools) from the surface.

I have two 1.5" intakes for my closed-loop and used to have the strainers. This used to catch snails. This works much better.

That's pretty slick. How is it mounted? Do you have a picture of it in your tank?

 

[Slickdonkey]

<a That's pretty slick. How is it mounted? Do you have a picture of it in your tank?

Well they don't call me the Slickdonkey for nothing :lol:

Here's a picture of it mounted in the tank.

Underneath the parts with no holes are the two 1.5" bulkheads. If you look at the previous picture I posted you can see some faint circles in red, those are little tabs that slip over the bulkheads. You don't want to use suction cups because they'll eventually fail. It took a lot of trial and error to get the measurement just right, but now it's pretty sturdy. You'd think it would just fall off but it doesn't.

Ignore the blue tint, I was screwing around with the white balance on my camera.

 

[cward]

That is great!!! Thanks for the pics.