PAR Monitoring Kit PMK - Neptune Systems

Click on image to zoom
View full size image

More Views

  • Discover the PMK - Neptune Systems Product Highlight

PAR Monitoring Kit PMK - Neptune Systems

100% Recommend this to a friend (10 of 10)

SKU: 209193
Please wait...


1-3 day service on orders over $249

What's this?

You could earn
1,495 points
($14.95 off a future purchase!)
Ships tomorrow

Quick Overview

Features and Benefits

  • Performs continuous light-level monitoring for your aquarium

  • Measures actual PAR – the light corals and plants use

  • Prevents burning out corals

  • Includes ASM – the new Advanced Sensors Module

  • PAR sensor hides nicely in aquarium inside Real Reef Rock

  • Fine tune your lighting to your aquariums needs


Ask a question

Product Questions

Have you guys used this product in your tanks with LEDs? Does it really work? How does it compare with the expensive PAR meter you guys have?

Question by: Emmanuel Becerra on Mar 23, 2016 12:55:00 AM
Great question!
We have used the PAR meter for Neptune systems in our T5 and Metal halide tanks with great success and it works as well as any PAR meter currently available. For LED PAR readings will be slightly off depending on what color LED is turned on and will not give 100% accurate readings for growth. You will want to consider the Seneye as an alternative option which has better reading of LED light. Feel free to let us know if you have any further questions!
Answer by: Connor (Admin) on Mar 23, 2016 10:50:00 AM
Do you have to buy one of the Apex systems in order to be able to use this? Or does it work on it's own?
Question by: Jamie Springer on May 26, 2016 8:32:00 PM
Hey Jamie!

Great question! You will need an Apex Controller in order to use the PAR Monitoring Kit.

Answer by: Randy (Admin) on Jun 2, 2016 11:55:00 AM
How long is the cable for the par meter?
Question by: Guillermo Ramos on Dec 10, 2016 10:37:00 PM
Great question! That cable is 15' in length. :-)
Answer by: Admin (Admin) on Dec 21, 2016 6:52:00 PM

Full Details

Neptune PMK Instructions


Continuous light-level monitoring for your aquarium

With the PAR Monitoring kit you can monitor and log your aquarium’s light levels 24 hours a day! The perfect tool to fine tune your lighting on your tank. Now you now can adjust your lights with the confidence of knowing you will not be giving too much or too little light to your corals and plants.

Prevent Burning Out Corals!

At certain parts of the specturm, the human eye cannot perceive light intensity changes once the light level exceeds a certain point. Too often this causes people to adjust their LED lights far past the ideal PAR level for their corals or plants. This usually results in burning, bleaching and/or death. With the PMK you can adjust your lights while monitoring exactly what light is affecting your corals and plants throughout the day. Also, not all corals are alike. Each type of coral has its own range of light intensity that makes it happy or not. 

Rugged Sensor Hides Inside Real Reef Rock

Sensors and probes are great in our aquariums, we just don’t want to see them! That’s why we usually put them down below in the sump. Not possible here. Knowing this we had the guys at Real Reef Rock design a custom piece of rock to hide the sensor in your aquarium. Now you can monitor light 24/7 and never see the sensor!

Measures Actual PAR – The Light Corals and Plants Use

The Apex with the PMK measures actual PAR. PAR stands for Photosynthetically Active Radiation. This is the light from 400 to 700 nanometers that organisms are able to use for photosynthesis – this includes the zooxanthellae algae that lives inside your corals. Other measurements like LUX are not useful at all as they measure just the light visible to the human eye.

24/7 Light Monitoring!

Track your light levels over time. With the PMK you track and log PAR 24/7. Now you easily go back and look at how you had your lights running last week. Even better you can compare your light output across the day with others who use the PMK and then compare light schedules and LED settings.

No more guesswork!

If you control your lighting with the Apex, you are in for an added bonus. The lighting wizard in Apex Fusion shows you your previous days light level across the day superimposed with the light wizard graph. Up until now you had to pretty much wing it when it came to making adjustments. Now you can easily make lighting changes and see the effects of those changes in one simple interface!  If you don’t have it already, this is one major reason to start controlling your lighting with the Apex. There are many Apex Ready light choices available. Some of the wireless lights like those from AquaIlluminations and EcoTech Marine even have their own Apex control modules (AWM and WXM).

Includes the newly released Advanced Sensors (ASM) Module!

More information will be released on this module in the future but in short this new module allows for hundreds of different types of future Neptune Systems and current 3rd-party sensors to be connected to your Apex and have their data logged.

Kit Includes:

ASM – Advanced Sensors Module

NPS – Neptune PAR Sensor

Real Reef Rock

6′ AquaBus Cable



10 Items

  • works as expected By Casey on 1/3/2017

    This thing is great. Everything you think this does, it does. It's really nice to be able to put this next to your light curves and see that it's working as expected.
  • Helped identify a long going problem with my tank By DRock on 12/4/2016

    When I first tried this product I thought it was defective. I am running Vertex illumina SR260 and a SR360 (two different tanks). With both fixtures I was only able to get PAR to around 160 at 12-15 inches below the surface of the water - this was with both running all three colors at 100%. The tank looked bright and light, but not getting anywhere near the PAR required for SPS which has been driving me crazy over the last four years. To test the equipment i took an extra Apex JR with my PAR meter to my LFS and took reading in their tank and was getting anywhere from 200- 600+ which is consistent with what they were getting with their PAR meter (confirmed my readings with the same Apex JR setup). After looking at this I ordered 4 Radion Pros to replace the two sub-par fixtures. Now i have two 36 inch expensive (about $4,000 spent on the two fixtures) LED fixtures that would be perfect for a fish only tank:(.
  • MUST MUST MUST have for SPS owners By BlennyKravitz on 10/19/2016

    Boy, is this thing humbling. I had my lights too far away from the surface and not turned up high enough. Chasing parameters and element dosing and the stupid AP700s were just too far away - lol. Like never revving past 3000RPM in a Porsche, but I have been putting race fuel in it and tuning it all this time…

    So far, Apex has been the best $1500+ investment I have made on this blasted hobby! Funny thing is, I went to the LFS last week to buy a fish trap and I ended with this Apex and a bunch of expensive coral - but I got the fish trap for free!

    Local LFS did not have PMK in stock and I am man of immediate gratification, so I came to BRS to see if they had a PMK available for next day air. I ended up finding SO MANY OTHER THINGS to buy that I missed the next day air cutoff. I replied to the confirmation email requesting to downgrade shipping to 2nd day air and not more than 5 minutes passed when I received a message that the they had confirmed the warehouse was still going to process my order and get it to me the following day.

    I placed the order in Los Angeles at 3:40PM and I was reading PAR levels the next morning by 11AM.

    three thumbs up to Neptune and BRS! I would give four, but the rock they gave me was too tight for the sensor. I foolishly jammed it in and it was extremely difficult and scary to remove, so make sure you can get it out if you want it out to attach to a PVC pipe to move around easily...
  • Love this product! By Mike on 10/14/2016

    I thought i was slowly killing my corals with too much light but after receiving the neptune PMK i found out i only had a par of about 100 at mid tank so i adjusted my kessil AP700's intensity to get mid tank level par to around 200 and after about a month all my corals which are mainly sps and a couple clams are looking better than ever with new growth. If you have LED's and an apex controller the PMK is a must have!
  • Great stuff! By Mike on 10/14/2016

    Good product a good price, you cant beat it. The mixing instructions were very easy to follow also.
  • Par monitoring kit By Kevin on 6/7/2016

    Neptune par kit is awesome it nice ti keep up with it in a sps tank
  • Great to tune lights By craig on 3/23/2016

    Those with reef tanks have probably spent a lot of time and money on selecting lights... this allows you to tune them for optimal coral health and map out tank to determine where corals will be happiest in the water column. If you have an APEX Controller, this is a nice upgrade. I found immediate benefit in the looks of the tank (I had lights on much too high)
  • Worth It!!! By XocyrusX on 2/8/2016

    I switched my tank around and suspended my light. No clue where to start if I didn't have this. Tested my old tank and matched my new one. Perfect! Moved corals over and will start ramping up till I see their sweet spot. Thanks BRS and Neptune!
  • No more guessing... By Matt K on 10/2/2015

    I had been loosing new corals rather quickly due to STN. I thought for certain I was 'shocking' them with my LED lighting. I was wrong about that!
    It's expensive. So are corals. Now that I know the corals are receiving enough light, I can look at other factors should I have any issues.
  • My Corals Love it. By Daquan44 on 9/13/2015

    Before installing this module, coral position and par were just a guess. Par meters were far to expensive for me to afford, but placing corals in my tank was hit or miss. When I saw this product I was happy there was an affordable option for me to measure par. More than just measure it, I could monitor it using my Apex. Immediately after installation I realized my Radions were dialed in too low. The PMK allowed me to adjust my Radions to meet the needs of the corals throughout the tank. At first I thought I was bleaching my corals because the tips were turning white on my sps. This was not the case. The corals began to grow at a rapid pace and the white tips are new growth. My a acroporas, montipora, and digitata have been doing extremely well since I began tracking par. My softies, esp the colt coral have always done well in the tank. This is a great Neptune product that every reefer should consider purchasing, and at this time there is no other product like it. There are cheaper par meters coming on the market lately, but none that allow you to monitor par 24/7, compare it electronically to your lighting schedule, graph it electronically, store it in a database, and control functions based on par like the Neptune PMK module.