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Fishbulb2
12/26/2015, 01:15 PM
Hi everyone,

I'm trying to set up something similar to this were I'm using peristaltic pumps to perform automated water changes. I plan to run the tubing through wire channel to hide it and then I'll paint the channel to match the walls. I bought a lot of RO tubing, but this stuff is so inflexible, that I don't think there is a chance it will make the 90 degree turns tight enough for the channel bends. Has anyone else run into the problem and how did you solve it? Is there a better tubing?

http://www.reefcentral.com/forums/showthread.php?t=2113252&page=3

Would this be a bad option for any reason?
http://smile.amazon.com/ATP-Vinyl-Flex-Plastic-Tubing-Length/dp/B00E6BCV0G/ref=pd_sbs_328_1?ie=UTF8&dpID=41%2BHkZuKudL&dpSrc=sims&preST=_AC_UL160_SR158%2C160_&refRID=0GC4AP24P0KH5M4A8RHB

Thanks,
FB

slief
12/26/2015, 02:47 PM
RO tubing will work fine. You get some 90* John Guest style push lock fittings for the sharp bends if you need them. Just keep in mind that head pressure and fiction loss Impact perstaltic pumps flow and if you are using perstaltic pumps that aren't calibratable, there will be a difference between the flow in and out of your system. Also, cheaper peristaltic pumps have slight variences in flow from one pump to the next. The end result will be some salinity drift. As such, you need to keep an eye on your salinity if you're using pumps that can't be calibrated. If you are using the Litermeter 3, that is a great choice as they can be calibrated. Just be sure to keep up on the roller cleaning and calibrate every once in a while.

Fishbulb2
12/26/2015, 03:07 PM
RO tubing will work fine. You get some 90* John Guest style push lock fittings for the sharp bends if you need them. Just keep in mind that head pressure and fiction loss Impact perstaltic pumps flow and if you are using perstaltic pumps that aren't calibratable, there will be a difference between the flow in and out of your system. Also, cheaper peristaltic pumps have slight variences in flow from one pump to the next. The end result will be some salinity drift. As such, you need to keep an eye on your salinity if you're using pumps that can't be calibrated. If you are using the Litermeter 3, that is a great choice as they can be calibrated. Just be sure to keep up on the roller cleaning and calibrate every once in a while.

Thanks for the input slief. I bought a Neptune DOS and plan to monitor the salinity with their conductivity meter. I plan to just adjust the timing by a minute here or there to keep the salinity constant.

I think I will have to stick with the RO tubing. It's rigidity is what will prevent it from collapsing with the vacuum pressure. But the John Guest push-to-fit elbows will definitely not fit in the wire channels. Their pretty small and 3 sets of RO tubing is all that will really fit (saltwater in, saltwater out, and DI water). I will have to get airline elbows instead. They'll restrict the flow a tiny bit, but they are tiny and fit well into the channels. I got some channel elbows and testing the tubing as is. I think it will kink over time without some aid at the 90 degree bends.

I'll post pics as I play.

FB

slief
12/26/2015, 03:17 PM
Thanks for the input slief. I bought a Neptune DOS and plan to monitor the salinity with their conductivity meter. I plan to just adjust the timing by a minute here or there to keep the salinity constant.

I think I will have to stick with the RO tubing. It's rigidity is what will prevent it from collapsing with the vacuum pressure. But the John Guest push-to-fit elbows will definitely not fit in the wire channels. Their pretty small and 3 sets of RO tubing is all that will really fit (saltwater in, saltwater out, and DI water). I will have to get airline elbows instead. They'll restrict the flow a tiny bit, but they are tiny and fit well into the channels. I got some channel elbows and testing the tubing as is. I think it will kink over time without some aid at the 90 degree bends.

I'll post pics as I play.

FB
The Dos is calibratable and a great choice. You should be able to calibrate each head perfectly if you calibrate using the tubing routed just as it will be when you are using it for your water changes. If you calibrate it like that, you will not need to worry about salinity drift.

I'd be leery of the airline elbows. Most of those are pretty thin and may not be a great long term solution plays they will reduce the line diameter quite a bit. They also aren't designed for RODI tubing so I would be concerned about the potential for leaks with tubing that isn't pliable. You can try heating the RODI tubing and see if you can bend it. If you add a bit of sand inside the tubing where you need the bend, that will allow you to bend the tubing using heat without kinking it at the bends.

Fishbulb2
12/26/2015, 06:27 PM
I'll try heating before cutting the tubing and using the airline tees. Heating should work well. It's likely to be about a 50ft run, I doubt I would be able to pack it with that much sand. And if I cut it, well then I would just have to splice it with an airline connector. I'll heat and test.

Thanks again.

cilyjr
12/27/2015, 07:52 AM
Drip irrigation connectors. They are made for pressure and fit on 1/4 line. Can get at Lowe's or home Depot where you get sprinkler stuff.
http://ecx.images-amazon.com/images/I/31FQDp5SWgL._AC_UL160_SR160,160_.jpg