Algae Scrubber Basics 3 of 14
Posted 02/19/2012 at 09:30 AM by Floyd R Turbo
[b]Fasteners[/b]
Most people have uses standard zip-ties to secure the screen to the slot pipe, since they are cheap and easy to use. Generally you have to use new ones each time you clean the screen (because you have to cut them), or you can re-use them if you’re handy with the tip of a razor blade and can get them to release.
You can also use releasable zip ties (I found them in the electrical section of Home Depot), but they’re not as easy to release as you would think they would be, unfortunately. I have used them, and I still need a mini-screwdriver to take them off.
Velcro straps can also be used, however they need to be free of adhesives, and I have never been able to get an answer from manufacturers about the stuff that has hooks on one side and loops on the other (such as OneWrap) regarding their safeness in aquaria. “Medical Grade” would be the safe way to go, but I haven’t looked much into those.
Another method of holding the screen in place is to use plastic shower curtain rings. It works very well, however you should have extras on hand in case one breaks when you’re removing it.
Yet another is to use sections of PVC pipe, one size larger that the slot tube, to make rotatable rings. This works very well, just make them narrow so that they don’t block too much flow.
[img]http://i611.photobucket.com/albums/tt191/FloydRTurbo/2011%20Aquarium%20Pics/Miscellaneous/ATS%20Designs/AS_waucedah_joe.jpg[/img]
The best one that I have found to date is the nylon [i]beaded cable tie[/i], which, like the zip-tie, is inert, but super-easy to release, so it’s good for months and possibly years. I haven’t seen these in any store, I had to order them online.
[IMG]http://i611.photobucket.com/albums/tt191/FloydRTurbo/2011%20Aquarium%20Pics/Miscellaneous/ATS%20Designs/Beadedzipties.jpg[/IMG]
The ones I bought are perfectly sized to fit around a 1” PVC Schedule 40 pipe. [b]These are my personal favorite choice.[/b] If you hang the screen only from the center (with the screen touching the top inside of the pipe) then these might not work very well. Instead, use them at the corners of the screen. Another nice this is that the beads are just a little bigger than the #7 mesh screen holes, so you can just push them through very easily.
[b]TIP:[/b] This is an important point – if you have a screen or screens that are held in place in the center of the pipe (or anywhere away from the ends) you do not want to cinch cable ties down hard! Since there is a slot cut in the pipe, cinching down the ties will cause the pipe to pinch closed and you will get reduced flow in the center. The zip-ties should just be snug enough to hold the screen in place.
I’ve seen a few designs that don’t use fasteners, but there are considerations to make with these designs.
[b]Preventing water creep along the pipe[/b]
This is an important part of the slot pipe design. The issue here is that when you are running water though a horizontal pipe with a slot in the bottom of it, the water has a tendency to creep along the bottom edge of the pipe, not matter how perfectly horizontal you install it. If your Algae Scrubber is positioned completely over your sump, this may not be a big issue, as any errant flow will just drip into the sump. If your pipe ends extend close to the edge of the sump however, a steady trickle of water can result in gallons of water on the floor. I can attest to this.
The solution is very simple. Right at the point where the slot ends, place a large plumbing gasket, such as an o-ring (use several, they’re cheap), or even a bulkhead gasket. The point is that it needs to prevent water from getting past it. I can tell you from experience that a standard zip-tie will not work – the profile is too low.
In many cases, you need to put this piece on the pipe before you weld the cap on the end of the pipe, or else it will be very difficult to install. This one is a ballcock washer, and definitely needs to be installed before the cap is installed:
[IMG]http://i611.photobucket.com/albums/tt191/FloydRTurbo/2011%20Aquarium%20Pics/Miscellaneous/ATS%20Designs/ballcockwasher.jpg[/IMG]
Here’s what I used on the latest mod to the Algae Scrubber I run
[IMG]http://i611.photobucket.com/albums/tt191/FloydRTurbo/2011%20Aquarium%20Pics/Customer%201%20-%20125%20Reef/2011-12%20Tank%20Build/DSC03630.jpg[/IMG]
I found these at Ace hardware in the plumbing gasket section. I forgot to put them on before solvent bonding the ends on, but luckily they were flexible enough to get over the end cap. They work fantastic!
Most people have uses standard zip-ties to secure the screen to the slot pipe, since they are cheap and easy to use. Generally you have to use new ones each time you clean the screen (because you have to cut them), or you can re-use them if you’re handy with the tip of a razor blade and can get them to release.
You can also use releasable zip ties (I found them in the electrical section of Home Depot), but they’re not as easy to release as you would think they would be, unfortunately. I have used them, and I still need a mini-screwdriver to take them off.
Velcro straps can also be used, however they need to be free of adhesives, and I have never been able to get an answer from manufacturers about the stuff that has hooks on one side and loops on the other (such as OneWrap) regarding their safeness in aquaria. “Medical Grade” would be the safe way to go, but I haven’t looked much into those.
Another method of holding the screen in place is to use plastic shower curtain rings. It works very well, however you should have extras on hand in case one breaks when you’re removing it.
Yet another is to use sections of PVC pipe, one size larger that the slot tube, to make rotatable rings. This works very well, just make them narrow so that they don’t block too much flow.
[img]http://i611.photobucket.com/albums/tt191/FloydRTurbo/2011%20Aquarium%20Pics/Miscellaneous/ATS%20Designs/AS_waucedah_joe.jpg[/img]
The best one that I have found to date is the nylon [i]beaded cable tie[/i], which, like the zip-tie, is inert, but super-easy to release, so it’s good for months and possibly years. I haven’t seen these in any store, I had to order them online.
[IMG]http://i611.photobucket.com/albums/tt191/FloydRTurbo/2011%20Aquarium%20Pics/Miscellaneous/ATS%20Designs/Beadedzipties.jpg[/IMG]
The ones I bought are perfectly sized to fit around a 1” PVC Schedule 40 pipe. [b]These are my personal favorite choice.[/b] If you hang the screen only from the center (with the screen touching the top inside of the pipe) then these might not work very well. Instead, use them at the corners of the screen. Another nice this is that the beads are just a little bigger than the #7 mesh screen holes, so you can just push them through very easily.
[b]TIP:[/b] This is an important point – if you have a screen or screens that are held in place in the center of the pipe (or anywhere away from the ends) you do not want to cinch cable ties down hard! Since there is a slot cut in the pipe, cinching down the ties will cause the pipe to pinch closed and you will get reduced flow in the center. The zip-ties should just be snug enough to hold the screen in place.
I’ve seen a few designs that don’t use fasteners, but there are considerations to make with these designs.
[b]Preventing water creep along the pipe[/b]
This is an important part of the slot pipe design. The issue here is that when you are running water though a horizontal pipe with a slot in the bottom of it, the water has a tendency to creep along the bottom edge of the pipe, not matter how perfectly horizontal you install it. If your Algae Scrubber is positioned completely over your sump, this may not be a big issue, as any errant flow will just drip into the sump. If your pipe ends extend close to the edge of the sump however, a steady trickle of water can result in gallons of water on the floor. I can attest to this.
The solution is very simple. Right at the point where the slot ends, place a large plumbing gasket, such as an o-ring (use several, they’re cheap), or even a bulkhead gasket. The point is that it needs to prevent water from getting past it. I can tell you from experience that a standard zip-tie will not work – the profile is too low.
In many cases, you need to put this piece on the pipe before you weld the cap on the end of the pipe, or else it will be very difficult to install. This one is a ballcock washer, and definitely needs to be installed before the cap is installed:
[IMG]http://i611.photobucket.com/albums/tt191/FloydRTurbo/2011%20Aquarium%20Pics/Miscellaneous/ATS%20Designs/ballcockwasher.jpg[/IMG]
Here’s what I used on the latest mod to the Algae Scrubber I run
[IMG]http://i611.photobucket.com/albums/tt191/FloydRTurbo/2011%20Aquarium%20Pics/Customer%201%20-%20125%20Reef/2011-12%20Tank%20Build/DSC03630.jpg[/IMG]
I found these at Ace hardware in the plumbing gasket section. I forgot to put them on before solvent bonding the ends on, but luckily they were flexible enough to get over the end cap. They work fantastic!
Total Comments 0
