luvreefs23
New member
Thanks, I don't think I'll be making that work. To big not to mention the adapters I'll need for 3/4"
Neptune Systems FMM/FMK
- Thread starter EDAT6
- Start date
luvreefs23
New member
Can you use this thing without the two unions?
jason2459
Well-known member
As long as you can get one side of a fitting to be BSPP threaded or sealed to it you don't have to use their union.
luvreefs23
New member
So I can't go to lowes and buy a 1" slip by female thread elbow and thread one end into it and the other into a slip by female coupler?
NPT (US standard) and BSPP are slightly different - former is tapered with slightly different angles to the threads. I have used standard NPT female fittings on BSPP males, but the fit is not as good. I have to wrap a lot of Teflon tape or use a lot of thread sealant to get a good seal. I would think you could find BSPP female couplings online.
gcarroll
Active member
I have always heard these types of meters eat up 8-10%. That in your case would be dead on if you expected 1300 gph.
I don't think it's that much. Trouble with the 'math' is variability. I read that these flow sensors are plus/minus 3%, so that means my actual flow could be as high as 1,236 or as low as 1,164. The RC head calculator is also not 100% accurate, failing to take into account 'nuances' in plumbing.
I run my tank with dual herbie drains, and allow a tiny trickle into the open channel/emergency. After the flow sensor installation, that trickle mostly dried up. How much is that trickle over the course of an hour - my guess is 10, maybe 20 gallons. So roundabout math suggests the sensors 'cost' about 2%.
Would like to hear others experiences.
If you upsize the sensor, the difference not really a detectable amount. If you same size, you might get a couple of percent.
If I read the post above correctly, he said he estimated a 10gph reduction. That is actually less than 1%, not 8-10%, right?
jason2459
Well-known member
ca1ore has it right you definitly want to go up a half size if possible if any kind of head pressure is a concern. Why having a 3/4" and a 1.5" option would be very useful.
I found no impact using the 2" flow meter on my 1.5" return plumbing. And of course I found no impact using the 1" on my skimmer using 3/4" plumbing but a much more restrictive mazzei injector.
I found no impact using the 2" flow meter on my 1.5" return plumbing. And of course I found no impact using the 1" on my skimmer using 3/4" plumbing but a much more restrictive mazzei injector.
jml1149
New member
EDIT: Nevermind, I see this is for your UV
Is this off your return pump?
I had the same concerns, I use a Sicce 5.0 with a 3/4" return, so I got a 3/4" threaded to 1" slip adapter for the pump output, tied in the 1" sensor, ran 1" PVC to the top of the tank, and then used a 1" to 3/4" elbow to continue on from there.
I have small kids, so my tank is fairly low. I can just BARELY fit my SWC skimmer underneath the sump, so it's tight. I thought it would be really tough to fit the sensor in, but wasn't so bad when I laid it all out. They can be installed horizontally or vertically, so there's a way to make it work somehow
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jml1149
New member
I didn't have a reliable method to calculate flow before the FMM install, and your use of the herbie trickle as a way to estimate is pretty clever.
When I installed, I did increase the size of the return pipe from the pump to top of sump from 3/4" to 1" so that probably had a small positive impact. Immediately after the install, the water level in my sump had not changed appreciably, so I believe the net delta flow loss is the same as the difference in increasing from 3/4" to 1" for a foot and a half or so, not including the FMM connections. Pretty small.
After, I also learned that my flow was WAY to low. I was using a ball valve to stop it down, because when I set it up I was blowing sand everywhere. My flow was ~ 250 gph on a 120g tank. Wow. Had I known before, I would have cut out the ball valve and just let it go. I've since opened it up all the way and get 450 gph and have noticed a significant improvement. Mostly I believe this effects my skimmer operation, as it's been MUCH darker and MUCH stinkier since I opened it up.
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jml1149
New member
Meh. I hate Teflon tape on plastic. My wife fell in LOVE with a bathroom set from Ikea, and they use metric fittings. Did not realize this at the time. Ripped old bathroom out. Installing new bathroom, over Teflon taped a plastic fitting on sink drain and cracked it. Took two weeks to get new fittings in from local plumbing house. Long time to go with no bathroom sink.
Plumber at the shop told me he never uses Teflon tape on plastic fittings for just that reason and thread sealant is better. I didn't have a problem using thread sealant on any of these sensor installs, for what it's worth.
jason2459
Well-known member
Pipe paste sealent is good for when the fitting threads match.
But when they don't like going from BSPP to NTP the tape wrapped around many many times is better. I did this with my jebao dct 15000 and worked fine but not suggested.
If using the supplied unions or BSPP to BSPP or NTP to NTP then I prefer paste.
But when they don't like going from BSPP to NTP the tape wrapped around many many times is better. I did this with my jebao dct 15000 and worked fine but not suggested.
If using the supplied unions or BSPP to BSPP or NTP to NTP then I prefer paste.
LobsterOfJustice
Recovering Detritophobe
Can link to an example of "thread sealant"? I have used teflon tape since getting into the hobby and, although I dislike threaded fittings in general, haven't had any issues. I tried teflon paste one time and it was awful.
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jml1149
New member
jason2459
Well-known member
jml1149
New member
Yeah the Ikea stuff was really cheap plastic, I should have known better than to try and torque it down so hard, but oh well.
jml1149
New member
This is what I use PTFE blue monster NSF food safe
You win. That is way more awesome.
The makers of plastic fitting don't recommend tape because you run the risk of cracking the female fitting. Having said that, I also use tape exclusively; I'm just very careful to not overtighten the fittings. I have cracked a few over the years, but not many.
