I'm going to be setting up a new tank soon, and I think I'm going to put a closed loop in there.
Now, the one thing about a closed loop that I don't like is the use of small strainers on the intake, like this one:
(https://www.ovas.ca/forum/proxy.php?request=http%3A%2F%2Fi174.photobucket.com%2Falbums%2Fw107%2FFunkmotor%2Fforsale%2FFT8641_99.jpg&hash=ea8e50e2439d9da7881c0c815162c2a2e3e9c5d5)
What I want is something that will fit on a standard bulkhead, but have much more surface area...like a ball or something that looks like a thick disc...so that things like wandering anemones don't get sucked in.
Obviously it would need to be cleaned at some interval, so some sort of quick-connect or other feature would be excellent.
I believe I have seen such a thing before, but now I cannot for the life of me find it. Anyone know what I'm talking about?
check out this thread... not sure if it helps but its a start... Its near the bottom of the page next to the cell phone.
http://www.reefcentral.com/forums/showthread.php?t=1688939
YES! That's it!
http://www.flexpvc.com/cart/agora.cgi?product=BulkheadFittingScreens
You are better to increase the number of intake feeds and use egg crate to avoid critters, you get better filtration and better coverage and less velocity. if you use fine filters they will clog.
I ordered some of those strainers from FlexPVC and I received them today.
They're big. 6" in diameter...but only about 1.5" thick. Combined with the 2" bulkheads, these will handle all the flow I need without creating any overly aggressive suction. I reckon with 2 of these inputs on my closed loop, even a BTA walking across one of them wouldn't be bothered by it.
Anyway, here's lots of pics. You can see the brass nuts in the bulkhead...they will have to go, which means I'll have to figure another way of keeping the strainer attached...it needs to be snug to the glass, as you can see.
(https://www.ovas.ca/forum/proxy.php?request=http%3A%2F%2Fi174.photobucket.com%2Falbums%2Fw107%2FFunkmotor%2FFish%2FStrainer%2FDSC00767.jpg&hash=00db6bb2a8d0373f218062663ae6460999501af9)
(https://www.ovas.ca/forum/proxy.php?request=http%3A%2F%2Fi174.photobucket.com%2Falbums%2Fw107%2FFunkmotor%2FFish%2FStrainer%2FDSC00768.jpg&hash=63f66b46655041d1e7fd9429d5ac650db40b3dbf)
(https://www.ovas.ca/forum/proxy.php?request=http%3A%2F%2Fi174.photobucket.com%2Falbums%2Fw107%2FFunkmotor%2FFish%2FStrainer%2FDSC00769.jpg&hash=ef1b8f93ff272db306cc87bf93cd3179c3892d46)
(https://www.ovas.ca/forum/proxy.php?request=http%3A%2F%2Fi174.photobucket.com%2Falbums%2Fw107%2FFunkmotor%2FFish%2FStrainer%2FDSC00771.jpg&hash=1e7159d06a99e4171f4f491ac93e85366191280c)
(https://www.ovas.ca/forum/proxy.php?request=http%3A%2F%2Fi174.photobucket.com%2Falbums%2Fw107%2FFunkmotor%2FFish%2FStrainer%2FDSC00772.jpg&hash=716df8923af59c5d7dd6bcbcac80238c47fd065e)
(https://www.ovas.ca/forum/proxy.php?request=http%3A%2F%2Fi174.photobucket.com%2Falbums%2Fw107%2FFunkmotor%2FFish%2FStrainer%2FDSC00773.jpg&hash=6d34fbc728064002f809690051df8ffd438f1183)
those are some sweet strainers
are the brass nuts embedded?
looks like the female part is, in the bulk head.
They were pressure-fitted in there. All I had to do was put in a screw and keep turning it until the brass nut was extracted. Not that hard at all.
What I might do now is drill /file the various pieces so that I can fit them with magnets. That will allow me to reach in and quickly swap out the strainers for cleaning.
It might be easier to simply glue a couple of pins onto the black portion of the strainer that will fit into the holes that you pulled the plugs from, finding sealed magnets that size might be tricky, it will be on a suction feed so the screen is unlikely to to fall off.
I like that idea, I was thinking of something simmilar.
Quote from: Contains Moose on October 31, 2009, 01:40:19 AM
It might be easier to simply glue a couple of pins onto the black portion of the strainer that will fit into the holes that you pulled the plugs from, finding sealed magnets that size might be tricky, it will be on a suction feed so the screen is unlikely to to fall off.
I had thought of that, but then I thought that the suction won't be all that powerful because the strainer is so large.
Even if it were more than I think it would be there's always the chance that something will be able to pull it off or knock it off...so I think having the extra measure of holding power would make it just that much more safe. The last thing I need is a prize fish - or a big snail - getting sucked into the pump.
true it is large but if you count the holes and do the math it will have lots of suction.
Quote from: Contains Moose on October 31, 2009, 05:27:48 PM
true it is large but if you count the holes and do the math it will have lots of suction.
I was never that good at math, care to indulge us?
Sure I can, what pump are you using? what size are the holes in the screen, it needs to be a fairly accurate dimension.
Do you have two bulkheads joined together to the pump sharing the same 2" line?
Quote from: Contains Moose on November 01, 2009, 02:39:59 AM
Sure I can, what pump are you using? what size are the holes in the screen, it needs to be a fairly accurate dimension.
The holes in the screen are 3/32" each. I'll be using 2" pipe from both bulkheads down to a Y connection, after which it will meet up with a Sequence Dart Gold running at 3,800 GPH. (Now that's at zero head, so I'd add a couple feet of head loss just from the pipes...so let's say 3,500 GPH is more realistic.)
You can see the pump curve here: http://ottawainverts.com/shop/product_info.php?cPath=568_52_589&products_id=5520
Then we go to a 1.5" output that will split into 2 final lines. I have not yet decided if I'll go with a Oceans Motions 4-way or something else to accomplish that.
As for the number of holes in the screen, you could probably work that out more simply than actually counting them.
I guess there are a couple of ways of looking at it, splitting to two 2" inlets to the pump is a great idea, it reduces the pumps velocity to 25% of what it would normally show, in order for the screens to be neutral resistance they would need to be a total of 940 holes , the slightest restriction would increase that number dramatically, and then there is a huge friction loss because of the thickness of the plastic that the holes are going through. Likely the pump will be perfectly ok but there will still be some suction force preventing the screens from falling off, you can do the test, run the pump and remove the screen, if you feel no resistance then I am wrong but I would be willing to bet there will be some resistance.
I don't like micro screens, I prefer a minimum of 3/16 square openings, I also prefer to see multiple feeds so you remove detritus from many areas in the tank, shove it through the closed loop and get it back into the water column.
Your head loss is correct, it will be minimal unless you use a ton of elbows on the returns, not likely you need to know but if you use locline you will need a minimum of 5 in order not to choke the pumps capacity even if you use the splitters, they still are only 3/4,keep it simple shove an OM4 on there and have an efficient and clean look.
Quote from: Contains Moose on November 01, 2009, 06:26:31 PM
I guess there are a couple of ways of looking at it, splitting to two 2" inlets to the pump is a great idea, it reduces the pumps velocity to 25% of what it would normally show
Wouldn't splitting the input in two, cause a 50% flow reduction?
Quotein order for the screens to be neutral resistance they would need to be a total of 940 holes
How's that work? And what is neutral resistance?
Quote
not likely you need to know but if you use locline you will need a minimum of 5 in order not to choke the pumps capacity even if you use the splitters, they still are only 3/4
Please explain.. i'm not sure what you mean "choke the capacity", nor do I understand how you get to 5 being a minimum...
Quote from: HookupWouldn't splitting the input in two, cause a 50% flow reduction?
I am assuming this is a pump that has a 1 1/2 " inlet or has the capacity to be reduced to 1 1/2 if installed as a closed loop pump.
Quote from: HookupHow's that work?
It's math' areas of holes, friction of holes etc, whenever possible it should be greater than the area of the pumps intake area.
Quote from: HookupAnd what is neutral resistance?
It's when the intakes in the tank along with all fittings and elbows are equal to the area of the pumps intake, not less or more.
Quote from: HookupPlease explain.. i'm not sure what you mean "choke the capacity", nor do I understand how you get to 5 being a minimum...
Loc-line is 3/4 diameter at it's best, when you take it's true area and friction you would need to have at least 5 to handle the output area of the pump assuming it is also 1 1/2.
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Moose, you're right to guess that I was intending to use loc-line to direct my inlets, and 5 sounds like a good number. Certainly gives me more to think about, though.
If I were to choke things back a bit by only having the 4 outlets, then it would be less stress on the strainer(s). Really, lots of people run closed loops so I know it's not armageddon even with the normal strainers, but my biggest fear is sucking in a wandering anemone and crashing my tank.
Of course, with that I could always get an 8-way. Have to go with a custom tank, then, though...as I'd certainly want to drill through the bottom and even in through the euro-bracing to get the outputs spread out the best I could.
It's all food for thought, I suppose. I just want to be sure I'm doing it right.
The comment about using 5 Loclines on the outputs was directed more towards a simple closed loop with no other device, if you planned on a 4 way then you would need a pair of Locline on each outlet with the proper plumbing to get the max out of the pump, if not then why waste the money on a pump that size.
Many get confused into thinking that two 3/4 outlets are the same as 1 1/2, but when dealing with areas it is a different story, you need two 3/4 Locline to handle the flow from a 1" pipe, and 5 for a 1 1/2" pipe.
The same is applied to inlet feeds for the pump, the more you have the better, the bigger the better, you get better coverage in the system with more and reduce the intake velocity considerably, If possible direct the inputs so that they add to the existing flow rather than fighting the flow pattern you want to achieve.
If you fed the outlet of a pump across the tank and had the inlet at the opposite end then you would achieve the maximum flow possible on a C/L