Apex Salinity Probe yes or no
 

Are they really worth buying? Heard mixed reviews that many don't work properly and are a waste of money. I'm worried that having a top-off system now if a leak happens or skimmer overflows the salinity will go out of whack. Any recommendations?

That happens anyway, whether you measure it or not. If you top off too much then your salinity will go down.

Those things are useful to get a quick look at the salinity in your system. And you know when you see a reading that just doesn't look right. But I would never in a million years rely on it to automate anything. ATO should run on a float switch, not a salinity meter.

Personally, I'd skip it. There is a lot to buy, probe, PM2, additional temperature probe, temperature probe calibration thermometer, salinity probe calibration solution (needs to be calibrated often).

I bought it before doing proper research and realizing what a pain it would be. If I could do it over, I'd skip it.

I've been using the salinity probe with my Apex for years now. It works and works well. You should calibrate it every so often to insure it's accuracy as it can and will stray over time. I just calibrated mine after a year or so since the last calibration and it only takes a minute to do. I use the same 53mS calibration solution that I use for my refractometer. The PM2 along with the CondX and temp probe is a bit of costly upgrade but for me, I have too much invested in my system to not take advantage of this feature. I also use several fail safes on my system and this is one of them. I have a very large tank and my Apex system is very complex with 7 EB8's and over 40 active outlets, PM1, PM2, VDM, Lunar Modules, Break Out Box, PH, ORP, CondX monitoring, ATO control, Tunze control etc. As such, monitoring salinity is just one part of my approach to insure that my system is as safe as possible and at the end of the day, it was a small expense relative to the rest of my Apex system, let alone tank.

That said, I don't use the salinity probe as a method of measuring my salinity but instead use it as a fail safe for my ATO as well as for my Genesis Renew automatic water changer. If my salinity gets to high or too low according to the probe, an alarm will be set off along with email/text alerts. Too high or too low salinity shuts my automatic water changer off. Salinity too low shuts my ATO off. I also use redundant float switches for my Apex controlled ATO as well as separate float switches for too low of water level and too high of water levels in my sump. I also monitor for water on the floor and do so in multiple places including around my sump as well as in my shed where my water storage is. As such, water on the floor is part of my ATO programming. Lastly, I use a dosing pump for my ATO and a solenoid as a failsafe. The dosing pump insures that should something go wrong with my ATO, the process of adding water is slow enough to insure that I can resolve the issue before things get out of hand. The solenoid is run inline on the ATO inlet and insures that siphoning can't occur in addition to providing an additional failsafe should the ATO outlet ever fail.

Here is my ATO code..
Fallback OFF
If Outlet AddWater = ON Then ON
Defer 003:00 Then ON
If Outlet AddWater = OFF Then OFF
If Outlet Return = OFF Then OFF
If Outlet SumpFull = ON Then OFF
If Outlet SalinityLow = ON Then OFF
If Outlet WaterBug = ON Then OFF
If Outlet SumpTooFull = ON Then OFF
Min Time 015:00 Then ON

Damn, you have a fancy system. Is there anything else missing from your system? :)

That's what I have a dual float system. Just like Apex to throw an alarm or a few whistles if the probe detects any issues with the salinity. Looked at the cost for module and probe be around $205 which is in the ballpark of a decent refractometer. Would make me sleep more sound at night.

Good to know is my same intensions. How much does this upgrade cost and who has best price? Maybe someone will have a black Friday sale.

LOl.. I am sure I missed plenty in my list.. Been in the hobby for about 27 years now and I've had my 480 gallon display for about 20 years.. It's evolved a lot over the years and as such, my control and life support system has evolved and become substantially more efficient with time. It's one of those things that the status quo is only good for a limited amount of time and there is always something to update or upgrade. The good thing is that with time, my system has been refined such that it uses a fraction of the power that it once did while also gaining more flow, better filtration, better and more manageable ambient temperatures and enough fail safes and spare parts to insure that tank crashes are pretty much 100% avoidable.

My spare parts inventory is pretty substantial and includes a spare Apex brain, spare Reeflo Hammerhead return pump with unions installed , spare Reeflo Dart recirculation pump with unions installed, spare Tunzes, spare ATO pumps, spare Genesis Renew controller, spare float switches, spare fittings etc. My theory is that you can never be too prepared when it comes to fail safes as well as spares.

In all honesty, I don't remember what I paid but at a quick glance the prices seem to be substantially less than when I got mine which was when the PM2 was first released.

Here are some current numbers from Premium Aquatics.
PM2 $84.99
Lab Grade conductivity Probe: $124.99
Temp Probe: $29.99

American Marine Salinity monitor only requires one probe which has a built-in temp sensor while Apex requires two. I am not sure about RKE.

The Apex uses one sality probe with the separate temp sensor.. No idea why they do it that way but all their probes use the standard 2 pin BNC connector so there is some consistency with the board designs. My guess is that it also allows them a little more flexibility in their probe vendors and a little less complexity in their components. A conductivity probe with built in temp probe is obviously a more complex probe than a conductivity probe without built in temp and as such, that would eliminate a single point of failure and potentially a more costly probe.. Also, using the same model probe between the Apex brain and the PM2 keeps programming and calibration simplified.

I use it, but do not control with it, apart from killing my ATO if salinity drops rapidly. My ATO already has 2 safety shut-offs (water too high & top off pump on for more than a gallon at a time), so this is just a third measure to kill it if it falls below 1.019. I mix new salt with it too, temperature calibrated so I know I'm getting the same salinity as what's in the tank.

That would be one very expensive refractometer or one very large ballpark. They're usually 20 or 30 bucks for a good one.

So from what I'm reading most people use it for comparable observation not for trusting control. Does this mean spending over $200 is best used on some other reliable means? What is recommended other then using a basic refractometer? Thought using the apex would be nice to send emails and alerts but if its mostly false alarms can't justify spending that much?

It is great for sending alerts and for salinity related fail safes. I would not use it for 100% replacement of a refractometer or as your only measurement of salinity where the difference in .001 is something we really pay attention to. If you want your Apex to alert you of a salinity issue or shut down the ATO in the event of a major salinity change, then it's perfect for that but it's not something you would replace your refractometer with unless you are calibrating monthly or bi-monthly. Even then, having a refractometer as a checks and balance is something highly advisable. In fact, your refractometer is ultimately the best way to verify if your Apex CondX probe needs calibration.

As I noted earlier, the CondX probe is an integral part of my Apex early warning and failsafe programming. I really like having it as it adds piece of mind by providing separate automated solution to monitoring salinity in conjunction with the Apex which a refractometer can't provide.

They fluctuate with temp as well and you may be able to compensate with a function but IME they are worth every penny. I wouldn't rely on it but I would set it to alert me if something went out of range.

I would never run an automated water change system without one.

Same with ORP. Not really important but tells a story that otherwise wouldn't be told.

Does a TEMP probe have to be connected at all times or just when calibrating? I heard you can save the $30 and temporally plug one in for calibration. What I don't understand if the Apex is so sophisticated and great why doesn't it communicate to the main brain and retrieve the Temp numbers there? Seems like this apex module system is just a money making scheme to me.

It does.

That's incase you want a second temp probe. Just more options.

You can do that for calibration however, once you remove the temp probe from the PM2, you will loose the temp compensation feature which can and does make a difference when it comes to accuracy. Specific gravity changes with temperature and a variance of a couple degrees can swing the salinity accuracy by .001 or more. I think you would also need to disable temp compensation in the probe settings because when you remove the temp probe, you may get erroneous readings TempX instead of no reading.

I too have wondered why you can't use the primary temp probe but my guess is that the modules such as the PM2 and PM1 operate and collect data independently of the Apex brain so the salinity with temperature compensation is probably handled within the module itself and retrieved from there by the Apex brain. Thus the module needs the probe to accurately calculate salinity independent of the controller.

FWIW, the current cost for the PM2, CondX probe and temp sensor is much less now than when it first came out. I'm sure I paid $100 or more than the prices above. While it may seem like a money making scheme, Neptune is a business and unlike most other controller manufacturers, Neptune has serious overhead invested in R&D and software development to further the Apex's features and functions. If you think they sell that many PM2 modules and that they make a ton of money on these temp probes, I'd think again. They don't make you buy a temp probe as part of a money making scheme. It's an option that adds accuracy to the probes function and there is certainly a good reason why the module itself needs it's own temp probe. Same goes with the modules. These modules expand the Apex's capability without having to render Apex brains obsolete every year or two when a new feature is added. Instead they can release a new module to expand the Apex's capability. It's makes the Apex modular and keeps costs down for those that don't need all those capabilities and it provides options for those that do. In the end though, Neptune does need to make money with these things so they can keep their doors open and remain one of the best controller manufacturers out there.

I will also note that the cost of the PM2, temp probe and salinity probe are right in line with and or less than the cost of salinity modules for other popular controllers like the Reef Keeper. Heck, it's much less expensive to outfit the Apex with salinity capabilities than it is to do the same on the Profilux!! Frankly, for what it does, I think the Apex PM2/CondX Probe/temp probe is fairly reasonably priced at this stage.

Thanks for explaining it to me makes more sense now.

I've never got mine to read properly even though I have a second temp probe connected to it. I just use my refractometer.

I'll sell you the probe and module if you are interested

Either you all have a bad module/brain, or they've fixed this issue with the latest hardware? My base unit is 6 months old and I haven't had any issues using the PM2 module with the base unit's temp probe.

Really how much?

Couldn't you just move the temp probe to the pm2 and keep it there? You can change which probe is used to display temp with fusion right? And I think you can tell your heaters which probe to use. Of course, at the end of the day, it's $30. Pretty much spend that much every time I look at the tank lol!