PM-2 Conductivity/Salinity Module

[txfatcat]

We just ordered the PM-2 module and should be arriving Thursday. We ordered this module so that we could start keeping a tighter reign on our 210 gallon reef in order to prevent or forsee any disasters or problems before they become dire. I am not as educated when it comes to this and am looking for any best practices or thoughts as I want to become as educated as possible before the module and probe arrive. I have read some threads about calibration and I am thinking that like any probe, this will need to be calibrated. Is there calibration fluid I will need to get or is there another way to calibrate the probe? If anyone has any thoughts, comments, or information please let me know.

[Hawkdl2]

You will need a calibration solution. They are available from Neptune, Marine Depot and many other online retailers in small single use packets. Buy a couple since you will want to recalibrate from time to time. If you search earlier threads on this, you will find a link to a chemical supplier that sells liter quantities of the solutions for a reasonable price.

The best advice, however, is that once you get the probe and module up and running do not fall victim to overzealous real-time chasing of your tanks conductivity by constantly adding salt or RO/DO. It's normal for the probe readings to wander a bit and it's best to use the probe to monitor longer term drifts in your tank or as an alarm for drastic acute events such as an ATO failure.

[tzzhc4]

My advice would be to get the I/O Breakout module and a float switch. It is what I have used on my 200gal SPS reef for years. The float switch sits in my sump and is sensitive to about 1/8inch drop in water. Keeps my salinity constant and only requires regular cleaning I originally got it a few years ago for my AC3 and recently moved it to my Apex. Works great!

http://www.neptunesys.com/index.php?option=com_content&task=view&id=32&Itemid=40

http://www.autotopoff.com/misc/

[txfatcat]

We currently have a Breakout Box and use it for a couple of things at the moment. "Sump low" switch kills the main pumps in the even of a problem to prevent them grenading themselves. Sump High switch kills the calc stirrer in the event of a failure to keep it from getting out of hand and the last on the skimmer collector in the event of the float ball failing, kills the skimmer pump. We also have a water bug to sense when water hits the ground. We have been watching a learning with the probe and will come up with another system that will doses salinity/water to keep it in check.

It is nice as we have never really had this much control over our system nor really cared. We have some other things in store but takes time and more money.


We have a mechanical float from a ro/di system to top off water right now which is very little because the Kalk stirrer makes up for most of it.

[schwaggs]

If you are looking for consistant readings, you should connect a temperature probe to the PM2 for automatic temperature compensation.