Neptune apex FMM flow sensor accuracy

RicGio · 03/26/2018, 08:39 AM

I recently installed a Neptune Apex FMM with 1" flow sensor. I'm curious the units it reads out in (GPH? LPH?). My return pump is a panworld 100PXX running at about 12' of head with the discharge valve throttled to about 30% open. Design Max flow at 0' of head for the pump is 1200 GPH. The FMM is showing 750. There is NO WAY I'm flowing that much. Can anyone chime in on the accuracy of these things?

gargoylenest · 03/26/2018, 10:05 AM

simple calculus: measure the time it takes to fill a, lets say 5 gal bucket cause everybody got one laying around.
You now know that your pump makes a 5gal/(t)(time it took to fill in sec).
take 5, divide by (t), multiply 3600(3600 sec in one hour) and you can compare with what the sensor told you.

mcgyvr · 03/26/2018, 10:15 AM

They are supposedly reporting in GPH..

and
I don't see a mention of stated accuracy on their site anywhere which would lead me to respond with a "likely not that accurate"..
On "similar" flow sensors in the market I was able to find a -/+10% stated accuracy..

But yes.. as stated above you can check it fairly easily..

FullBoreReefer · 03/26/2018, 11:38 AM

The only real benefit I find with my flow meters and FMM is now I can get my flow close instead of guessing like before. To me it's better than nothing.

RicGio · 03/26/2018, 11:43 AM

Quote:

Originally Posted by FullBoreReefer

The only real benefit I find with my flow meters and FMM is now I can get my flow close instead of guessing like before. To me it's better than nothing.

Yeah. I suppose it's a good indicator of flow. I know what "normal" is now and I can use it as a comparison.

I don't know if I want to pull it out of my hard piped system and start filling buckets with my stopwatch quite yet...

RicGio · 03/26/2018, 11:46 AM

Quote:

Originally Posted by gargoylenest

simple calculus: measure the time it takes to fill a, lets say 5 gal bucket cause everybody got one laying around.
You now know that your pump makes a 5gal/(t)(time it took to fill in sec).
take 5, divide by (t), multiply 3600(3600 sec in one hour) and you can compare with what the sensor told you.

It's hard piped into my system. Not sure I want to yank it out and start filling buckets with it about now.

dfwn8 · 03/26/2018, 03:27 PM

Mine was nearly right on. I put my system in feed mode, then put a 1 gal container under the return nozzle and measured it there. mine however was much lower than I expected even though it was accurate. I have a COR20 pump.

Dross · 03/26/2018, 04:46 PM

How confident are you in the 12' of head? The 100PX-X produces almost no flow at that head. I cannot imagine you would be using it in that manner. I am not familiar with the FMM, but does the APEX automatically know the size of the meter or does it have to be configured somehow? If so, it might have the wrong size meter programmed.

kevin_e · 03/26/2018, 05:07 PM

Quote:

Originally Posted by RicGio

It's hard piped into my system. Not sure I want to yank it out and start filling buckets with it about now.

Another method then is to use a tracer (piece of food, paper, etc.). Something tiny that will get sucked up and spit out without harming the pump. Time it from when it goes in the pump, to when it comes out in the tank in seconds.

Take the feet of pipe length (12') and divide by the time in seconds. Then multiple by the cross sectional area of the pipe (0.26 sq ft). You will get a cubic feet/second discharge rate. Convert to gph with a converter calculator or do cross cancelation and conversion manually. Compare to the flow sensor.

Sent from my XT1080 using Tapatalk

FullBoreReefer · 03/26/2018, 05:11 PM

Quote:

Originally Posted by Dross

How confident are you in the 12' of head? The 100PX-X produces almost no flow at that head. I cannot imagine you would be using it in that manner. I am not familiar with the FMM, but does the APEX automatically know the size of the meter or does it have to be configured somehow? If so, it might have the wrong size meter programmed.

Depends how the FMM is configured. It can be set as "Auto" and it'll find the correct sensor.

Although, my 1/4" sensor always registers as a 1", stating it's 500+gph, so I go in and change it back to 1/4" and it drops back to my normal 5.3gph.

Bent · 03/26/2018, 09:06 PM

I’ve thought about these, and I truly don’t know the point. Why would you ever need to know exactly what the flow rate is and then monitor it on top of that?

FullBoreReefer · 03/26/2018, 09:29 PM

Quote:

Originally Posted by Bent

I’ve thought about these, and I truly don’t know the point. Why would you ever need to know exactly what the flow rate is and then monitor it on top of that?

Here's my setup and what works and makes sense to me for my setup.

My tank is going on 8yrs as a mixed reef, about 11yrs total. I've built things, boughten gadgets, have upgraded equipment over the years, and well, it's one of those thing for me that keeps the hobby fun...buying, building, tuning, and tweaking.

Why i "use" them...

3 - 1" sensors
*left return, right return, ATS flow.
**I am able to tune my return pump for "proper" sump turnover rates, I could I have only hooked one to my main return line, but my plumbing splits and isn't quite and even length on each side. Now I can be anal and tune my left to right flow rates; and the 3rd is for feeding flow requirements for the size of ATS screen I use for "proper" growth.

1 - 1/2" sensor
*hooked to my dual reactors for tuning reactor flow rates. Maximizing use of said dispensable product.

1 - 1/4" sensor
*hooked to my "pod/s" bucket; I grow pods in this bucket. I don't need to monitor this since it only flows at 5gph, but it was only $20 haha.

I feel like I am now able to shoot for manufacturer flow rate specs, weather it be chemicals or such in a reactor, or feeding another add on piece of equipment. Now taking and using a product to its full potential instead of guessing like the old days.

I can also be notified of an increase or decrease in flow. Such as the reactor material is clogging, flow decreases through the reactor, I get notified, I either inspect and clean, or take offline and replace. Or an animal somehow or does become sucked into your return pump, #1 do you have float sensors that text you when the sump rises? #2 now I'll get another notification stating my returns decreased. I now know where to look, or what to shut off. N the mean time, my skimmer is programmed to power off in such a situation, saving an overflow.

BUT...
Are they needed?? Heck no...but why not!?! I get bored with always just viewing and cleaning it. I need new toys to keep it fun, check my specs below, I don't want to sound like I'm bragging but I've slowly upgraded to better and better equipment over the years. All pumps are also Dc. I'm all running out of thing and room to expand.

So sometimes a fairly cheap gadget makes it fun again to tweak on things.

ca1ore · 03/27/2018, 07:05 AM

The FFM can be configured to display either LPH or GPH. I've found the sensors to be generally accurate.

ca1ore · 03/27/2018, 07:10 AM

Quote:

Originally Posted by Bent

I’ve thought about these, and I truly don’t know the point. Why would you ever need to know exactly what the flow rate is and then monitor it on top of that?

Certainly not a 'must have', but can be quite useful in certain circumstances. For example, I monitor the flow through my CaRx, and when the number starts to drop it's an indication that the media is getting clogged. I also monitor main return flow, which will tell me if the pump has become blocked or clogged. It's just another form of redundancy.

Member No. 1 · 03/27/2018, 11:23 AM

Quote:

Originally Posted by ca1ore

Certainly not a 'must have', but can be quite useful in certain circumstances. For example, I monitor the flow through my CaRx, and when the number starts to drop it's an indication that the media is getting clogged. I also monitor main return flow, which will tell me if the pump has become blocked or clogged. It's just another form of redundancy.

+1 - Same idea on the return, but I use a second one to monitor the flow thru my UV.

RicGio · 03/27/2018, 11:46 AM

Quote:

Originally Posted by Dross

How confident are you in the 12' of head? The 100PX-X produces almost no flow at that head. I cannot imagine you would be using it in that manner. I am not familiar with the FMM, but does the APEX automatically know the size of the meter or does it have to be configured somehow? If so, it might have the wrong size meter programmed.

Ooops. Typo. Too many x's. it is a 100PX

•Max Flow: 790gph
•Max Head: 21ft

I'm fairly confident with the 12' number. Sump is in basement and it is 8'rise to the return line. 1" PVC with Minimal fittings. 1 bulkhead, 1 90 ell, a gate valve and 2 45 ells.

I found the issue. It was set to Liters per hour. I switched it to GPH. All good. Reading 200 GPH which makes MUCH more sense!

RicGio · 03/27/2018, 11:50 AM

Quote:

Originally Posted by FullBoreReefer

Depends how the FMM is configured. It can be set as "Auto" and it'll find the correct sensor.

Although, my 1/4" sensor always registers as a 1", stating it's 500+gph, so I go in and change it back to 1/4" and it drops back to my normal 5.3gph.

My RODI output won't read on the 1/4" sensor. Too slow of a flow? It reads fine on the raw water input.

RicGio · 03/27/2018, 11:51 AM

Quote:

Originally Posted by Bent

I’ve thought about these, and I truly don’t know the point. Why would you ever need to know exactly what the flow rate is and then monitor it on top of that?

I want to set up an alarm to let me know when it stops or becomes restricted.

FullBoreReefer · 03/27/2018, 12:06 PM

Quote:

Originally Posted by RicGio

My RODI output won't read on the 1/4" sensor. Too slow of a flow? It reads fine on the raw water input.

I'd guess to slow or air bubbles stuck inside

reefinnewb · 03/27/2018, 12:13 PM

Can you put one on your overflows so if it goes below a threshold, to shut off the return pump?

Not sure if it's possible but seems like it would be a good use case.

FullBoreReefer · 03/27/2018, 12:17 PM

Quote:

Originally Posted by reefinnewb

Can you put one on your overflows so if it goes below a threshold, to shut off the return pump?

Not sure if it's possible but seems like it would be a good use case.

Very possible BUT I would go overkill and put the largest sensor you can fit. The impellers on the insides will cause an obstruction.

Member No. 1 · 03/27/2018, 12:17 PM

Quote:

Originally Posted by reefinnewb

Can you put one on your overflows so if it goes below a threshold, to shut off the return pump?

Not sure if it's possible but seems like it would be a good use case.

Overflows will work, but not a good idea. If it takes in air, or the drain line isn't completely full, you will get erroneous reading.

If you did however, you would want it to detect more flow, as that would mean more water is being pumped to the DT which could lead to an overflow.

Less flow would mean your return pump intake/output could be clogged or
the pump is on it's way out.

reefinnewb · 03/27/2018, 12:20 PM

Good suggestions!

It's my intention eventually. I'll have to work out all of the details when I get to that point.

ca1ore · 03/27/2018, 06:20 PM

You can put sensors on siphon drains but not open channels. I use one on my main siphon as well and it triggers a 'clogged drain' alert if the flow drops below my defined threshold. I don't use them to control anything because the sensors do periodically get jammed. I also have an optical switch mounted high in the overflow that will trigger if the water raises to the point that the emergency is getting material flow.

Feed Me Tacos · 06/14/2019, 06:13 PM

Quote:

Originally Posted by Member No. 1

+1 - Same idea on the return, but I use a second one to monitor the flow thru my UV.

What size flow meter and what are your flows?

I have 1" flow meters, both below the minimum spec for the flows being measured (150 gph min) I upgraded all my tubing to a larger size, which has helped A LOT. If I put the 1/2" meters in for the correct range, it'll be another HUGE bottleneck.

I'm showing 130 and 70 gph with 1" meters.

There is no way I'm going to get a larger pumps to push through a 1/2" flow meter without losing flow rate.

03/26/2018, 10:15 AM	#3
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	They are supposedly reporting in GPH.. and I don't see a mention of stated accuracy on their site anywhere which would lead me to respond with a "likely not that accurate".. On "similar" flow sensors in the market I was able to find a -/+10% stated accuracy.. But yes.. as stated above you can check it fairly easily.. __________________ Who me?

03/26/2018, 11:38 AM	#4
FullBoreReefer Registered Member Join Date: Jul 2010 Location: Wooster, OH Posts: 1,862	The only real benefit I find with my flow meters and FMM is now I can get my flow close instead of guessing like before. To me it's better than nothing. __________________ 60x36x24 mixed reef. 40b sump. Regal 250int Varios. 4xHydra26HDs+t5s. 4xMp40wes. Apex2016.

03/26/2018, 09:06 PM	#11
Bent I got nothin' Join Date: Nov 2004 Location: The anals Posts: 6,420	I’ve thought about these, and I truly don’t know the point. Why would you ever need to know exactly what the flow rate is and then monitor it on top of that? __________________ Quitters never lose. [QUOTE=CStrickland]Who gets mad at a starfish?[/QUOTE] Current Tank Info: 75g DT, 30G refugium, 10g chaeto tank, 50g stock tank basement sump

03/27/2018, 07:05 AM	#13
ca1ore Grizzled & Cynical Join Date: Apr 2006 Location: Stamford, CT Posts: 17,319	The FFM can be configured to display either LPH or GPH. I've found the sensors to be generally accurate. __________________ Simon Got back into the hobby ..... planned to keep it simple ..... yeah, right ..... clearly I need a new plan! Pet peeve: anemones host clowns; clowns do not host anemones! Current Tank Info: 450 Reef; 120 refugium; 60 Frag Tank, 30 Introduction tank; multiple QTs

03/27/2018, 06:20 PM	#24
ca1ore Grizzled & Cynical Join Date: Apr 2006 Location: Stamford, CT Posts: 17,319	You can put sensors on siphon drains but not open channels. I use one on my main siphon as well and it triggers a 'clogged drain' alert if the flow drops below my defined threshold. I don't use them to control anything because the sensors do periodically get jammed. I also have an optical switch mounted high in the overflow that will trigger if the water raises to the point that the emergency is getting material flow. __________________ Simon Got back into the hobby ..... planned to keep it simple ..... yeah, right ..... clearly I need a new plan! Pet peeve: anemones host clowns; clowns do not host anemones! Current Tank Info: 450 Reef; 120 refugium; 60 Frag Tank, 30 Introduction tank; multiple QTs

03/26/2018, 08:39 AM	#1
RicGio Registered Member Join Date: Oct 2002 Location: NJ Posts: 658	Neptune apex FMM flow sensor accuracy I recently installed a Neptune Apex FMM with 1" flow sensor. I'm curious the units it reads out in (GPH? LPH?). My return pump is a panworld 100PXX running at about 12' of head with the discharge valve throttled to about 30% open. Design Max flow at 0' of head for the pump is 1200 GPH. The FMM is showing 750. There is NO WAY I'm flowing that much. Can anyone chime in on the accuracy of these things?

03/26/2018, 10:05 AM	#2
gargoylenest Registered Member Join Date: Jan 2015 Location: montreal,canada Posts: 135	simple calculus: measure the time it takes to fill a, lets say 5 gal bucket cause everybody got one laying around. You now know that your pump makes a 5gal/(t)(time it took to fill in sec). take 5, divide by (t), multiply 3600(3600 sec in one hour) and you can compare with what the sensor told you.

03/26/2018, 03:27 PM	#7
dfwn8 Registered Member Join Date: Nov 2015 Posts: 9	Mine was nearly right on. I put my system in feed mode, then put a 1 gal container under the return nozzle and measured it there. mine however was much lower than I expected even though it was accurate. I have a COR20 pump.

03/26/2018, 04:46 PM	#8
Dross Registered Member Join Date: Jan 2016 Posts: 44	How confident are you in the 12' of head? The 100PX-X produces almost no flow at that head. I cannot imagine you would be using it in that manner. I am not familiar with the FMM, but does the APEX automatically know the size of the meter or does it have to be configured somehow? If so, it might have the wrong size meter programmed.

03/27/2018, 12:13 PM	#20
reefinnewb Registered Member Join Date: Aug 2005 Location: Macungie, Pa Posts: 167	Can you put one on your overflows so if it goes below a threshold, to shut off the return pump? Not sure if it's possible but seems like it would be a good use case.

03/27/2018, 12:20 PM	#23
reefinnewb Registered Member Join Date: Aug 2005 Location: Macungie, Pa Posts: 167	Good suggestions! It's my intention eventually. I'll have to work out all of the details when I get to that point.