Closed Loop intake filter

chrisguy · #1 07/18/2005, 10:22 AM

I have read as many articles on closed loops as I can find. I am planning on a closed loop for a 120 gal project that is currnetly in the works.

My question is what type of filter are you using on the intake side of the closed loop. I dont want to suck up (and blend) any of the shrimp/crabs that I have.

Thanks!!

Anthony Calfo · #2 07/18/2005, 01:07 PM

the intake for CL pumps are generally quite large ( to prevent cavitation of pump).

In guarding it... we are not trying to filter it, but simply block fishes, snails or like macroorganisms from entering. However... we do want microcrustaceans and plankton to pass through (no worries on impeller shear... a bunk concern/argument).

I just take gutter guard (coarse plastic mesh for screening rain gutters from leaves) and I roll a short length of it up to jam into the intake. Its so large and coarse that it could never really be clogged by algae, yet it easily prevents even small snails from passing through.

chrisguy · #3 07/18/2005, 01:53 PM

Thank you for the quick response. This was (hopefully) the last great hurtle I needed to get past.

Dazed And Confused · #4 07/18/2005, 04:11 PM

I found a couple of strainers made for spray tanks. Grids on them are large enough to allow water, plankton, etc. thru but too small to allow even a nassarius snail thru. They weren't but about $5 apiece, so I got a few so I can swap them rather than messing with cleaning them. They're threaded as well for easy changing.

captbunzo · #5 08/30/2005, 01:17 AM

Mr. Dazed & Confused - can you give us some more specific information on those strainers you are talking about here? Where one could get one? Brand, pic, link?

Thanks!

Dazed And Confused · #6 08/30/2005, 04:10 AM

I found these at a farm supply store. I assume you could also look at a company that handled spray equipment, etc. The store manager where I got 'em is a good friend of mine - I'll see if he can get me a manufacturer's phone number or website. These are about 5" in diameter, cone shaped and about 4" tall but I know they make a couple of different sizes. The opening is threaded and I used a reducer to make it fit the end of the pipe. Mine fit into my overflow fine and I have the second on the intake for the closed loop. Even a small nassarius snail can't get thru the holes. So far they're working great!

chrisguy · #7 08/30/2005, 07:02 AM

I ended up buying one of these. http://www.aquaticeco.com/index.cfm/.../8566/cid/2098

My original plan was to make a "t" fitting and use one of these on each end. http://www.aquaticeco.com/index.cfm/.../8573/cid/2020

My system is not up a and running yet, so I am not sure which will work best. Will know more in about 2 weeks when I do my first water test (in the garage).

captbunzo · #8 08/30/2005, 09:32 AM

Our closed loop - for a 90G tank - will have about 3000 GPH flowing through it. I haven't completely decided what to use yet for the intake and how many holes. The pump of choice is a Sequence Reeflo Dart. It has a 2" intake. That could be plumbed to one hole. However, I am concerned, even with that big wide strainer, about possible damage to fish.

One consideration I have had was to go with two 1.5 inch holes instead of one 2 inch hole.

chrisguy · #9 08/30/2005, 10:15 AM

I'll be using that exact same pump. Once my plumbing is complete I'll do a water test and try to post up what type of Intake filter I ended up using. Should be testing in about 2 weeks.

wstellwagen · #10 09/01/2005, 12:27 PM

I am interested as well I suspect fish will be ok as I had a 2" one in my sump feeding a hammerhead and it didn: bother the fish i had there
A 3" clown , a trigger and a large damsel .
The question is where to place and how to hide.

Walt

Ploppers · #11 09/14/2005, 10:30 AM

Quote:

Originally posted by chrisguy
I'll be using that exact same pump. Once my plumbing is complete I'll do a water test and try to post up what type of Intake filter I ended up using. Should be testing in about 2 weeks.

So did ya try it out yet?

Quote:

Originally posted by wstellwagen

The question is where to place and how to hide.

If you find some answers let us know.

I'm curiuos how people have hidden them or if there was a specific reason for placement. Also what about plumbing the intake of a dart over the top of a larger tank as apposed to drilling. Is it acceptable to plumb such a large intake this way or would it cause problems?

chrisguy · #12 09/14/2005, 10:49 AM

Sorry for the delays, I will be setting up the tank this weekend.

I water tested the tank for 3 days and prefered the look and function of the 2" intake filter. The filter worked without creating a heavy suction.

I painted the back of the tank a dark blue and the filter doesn't jump out at you. I'll post pictures early next week.

captbunzo · #13 09/14/2005, 11:16 AM

What sort of filtering did you end up using? Are we talking about one fo the ones above or some sort of guttter guard solution?

Also, pics man, WE NEED PICS!!!

Donw · #14 09/14/2005, 08:47 PM

Not sure I'm following this. But you need to split the flow for two reasons. If you suck on a big tang your going to burn up a pump and You will have alot less suction if its split.

Here's some pics
http://www.reeffrontiers.com/photos_...500&ppuser=356

http://www.reeffrontiers.com/photos_...500&ppuser=356

http://www.reeffrontiers.com/photos_...500&ppuser=356

Hope this helps
Don

chrisguy · #15 09/14/2005, 09:06 PM

I ended up using one of these. http://www.aquaticeco.com/index.cfm/.../8566/cid/2098

Donw - With this 2" filter the Tang would have to be about 8" long and capable of bending its bodie at two different places at about a 110 degree angle to block the filter. I'm not flaming, just trying to paint the picture of how truly big this filter is.

If a fish was stuck on the filter, I'm confident that it will not stop the flow of water to the pump.

Donw · #16 09/14/2005, 09:26 PM

Quote:

Originally posted by chrisguy
I ended up using one of these. http://www.aquaticeco.com/index.cfm/.../8566/cid/2098

Donw - With this 2" filter the Tang would have to be about 8" long and capable of bending its bodie at two different places at about a 110 degree angle to block the filter. I'm not flaming, just trying to paint the picture of how truly big this filter is.

If a fish was stuck on the filter, I'm confident that it will not stop the flow of water to the pump.

Its also about the fish. With a split intake the suction is reduced by 50%. Keeps the fish from sticking to the intake. Been there done that.

Don

Ploppers · #17 09/14/2005, 09:27 PM

Quote:

Originally posted by chrisguy
I ended up using one of these. http://www.aquaticeco.com/index.cfm/.../8566/cid/2098

Donw - With this 2" filter the Tang would have to be about 8" long and capable of bending its bodie at two different places at about a 110 degree angle to block the filter. I'm not flaming, just trying to paint the picture of how truly big this filter is.

If a fish was stuck on the filter, I'm confident that it will not stop the flow of water to the pump.

How big are the gaps in that strainer? Are they small enough to keep out small snails?

Qwiv · #18 09/15/2005, 12:35 PM

This is what I am planning on using

http://www.aquaticeco.com/index.cfm/.../8559/cid/2079

captbunzo · #19 09/15/2005, 01:25 PM

Quote:

Originally posted by chrisguy
I ended up using one of these. http://www.aquaticeco.com/index.cfm/.../8566/cid/2098

Ah - so they actually have these available for 1.5, 2, and 3 inch intakes. The first number is the pipe size it will fit onto. Now, there are some other numbers as well that don't really seem to make much sense.

For instance, for the 2" strainer, the description is: Strainers, 2" FNPT, 1/4" x 1".

I assume that 2" FNPT means a 2" pipe. So then, what does the 1/4" x 1" part mean?

Lastly, what are the actual dimensions of the strainer and which size do you have? I was thinking about using 2 intake holes for our closed loop, but may not since there is a 2" strainer available.

What is the diameter of the strainer, and what is the size from front to back?

Ploppers · #20 09/15/2005, 03:33 PM

Quote:

Originally posted by captbunzo

I assume that 2" FNPT means a 2" pipe. So then, what does the 1/4" x 1" part mean?

Could the 1/4" x 1" possibly be the size of the openings in the strainer?

chrisguy · #21 09/15/2005, 10:58 PM

The strainer is less than 5" diameter and just under 3.5" deep. The two rows of vents on the sides (not the flat face) are 1/4" wide and 1" long, so that might be the missing numbers.

Pics of the inside of the tank (no water). I used a 3" long 2" male to male adapter. I would have preferred something shorter but that is all I could find.

captbunzo · #22 09/16/2005, 09:32 AM

Thanks for the pics! They are definately nice.

I have pretty much decided to use 2 intake holes. I haven't decided, however, whether to use the big strainer (like you have) or the small pointy ones.

chrisguy · #23 09/27/2005, 11:46 AM

Little update. The tank has been up and running since 9/18. In this time I have observed that my two clown fish, each about 1.5" long swim in and around the intake filter without any issues. As a matter of fact many fish will swim around the filter at different times of the day without any ill effect. I even watched a sea urchin walk across the front. The suction pressure is minimal as the filter really disperses the intake pressure. I've added a couple pictures

Full tank:

Close up

captbunzo · #24 09/27/2005, 12:02 PM

Very cool! Thank you much for the updates and the pics!

raynist · #25 10/26/2005, 01:07 PM

Quote:

Originally posted by chrisguy
Little update. The tank has been up and running since 9/18. In this time I have observed that my two clown fish, each about 1.5" long swim in and around the intake filter without any issues. As a matter of fact many fish will swim around the filter at different times of the day without any ill effect. I even watched a sea urchin walk across the front. The suction pressure is minimal as the filter really disperses the intake pressure. I've added a couple pictures

Full tank:

Close up

I see that you are using the modular pipe attached to PVC, what size pvc are you using, and what size modular pipe? Did you have any trouble fitting the modular pipe to the PVC?

I am thinking about doing something similar with a 1" pvc pipe around the top of the tank.

Thanks
Ray Nist