Ato based on salinity? Any one tried?

dazza1304 · Post by **dazza1304** » Wed Aug 22, 2012 11:27 am

As above, the salinity probe seems quite accurate and was wondering has anyone use to control an Ato pump?

My thoughts are, when salinity decreases to a set level the Ato pump would operate until the salinity reached a target value and to be certain doesn't overfill have a timeout of 10 secs then a lockout so it doesn't operate again for maybe an hour or so?

You experiences/thoughts would be much appreciated!

lnevo · Post by **lnevo** » Wed Aug 22, 2012 12:11 pm

Conceptually I like it...no float switches needed, or just to prevent overflow if something does go wrong...wonder why no one else has thought of it...gotta be some gotcha somewhere...

DrewPalmer04 · Post by **DrewPalmer04** » Wed Aug 22, 2012 12:16 pm

I've thought of something like this...for mixing tanks.

Step 1: Figure out salt to water ratio for 1.026 salinity
Step 2: Add salt to tub...probe reads 0
Step 3: Pump adds water from RO/DI tub to salt tub until 1.026 is reached or ATO switch is reached with water..which ever is first (to avoid overflow)
Step 4: Waterchange mode via one ATO switch on sump..one in salt tub (or three ATO switchs ideally)

Just thoughts.....

dazza1304 · Post by **dazza1304** » Thu Aug 23, 2012 12:52 am

I cannot think of any reason it would not work, so how would I code this to check how it works?

Danne · Post by **Danne** » Thu Aug 23, 2012 3:59 am

You must start with water, then add salt. Otherwise the concentration will be to high and calsium will "fall out" as limestone.

dazza1304 · Post by **dazza1304** » Thu Aug 23, 2012 9:02 am

Danne wrote:You must start with water, then add salt. Otherwise the concentration will be to high and calsium will "fall out" as limestone.

Thanks for the reply, but I was referring to my original post:

"the salinity probe seems quite accurate and was wondering has anyone use to control an Ato pump?

My thoughts are, when salinity decreases to a set level the Ato pump would operate until the salinity reached a target value and to be certain doesn't overfill have a timeout of 10 secs then a lockout so it doesn't operate again for maybe an hour or so?

You experiences/thoughts would be much appreciated!"

DrewPalmer04 · Post by **DrewPalmer04** » Thu Aug 23, 2012 9:43 am

Now, would you want the ATO pump to kick on when salinity DECREASES? you would want fresh water to be added if the salinity increased...(say when you dose two part additives)

A decrease would mean you would want additional salt mix added via the ATO

dazza1304 · Post by **dazza1304** » Thu Aug 23, 2012 9:44 am

DrewPalmer04 wrote:Now, would you want the ATO pump to kick on when salinity DECREASES? you would want fresh water to be added if the salinity increased...(say when you dose two part additives)

A decrease would mean you would want additional salt mix added via the ATO

Yes, your correct!! I got it wrong - it should be as you say, when the salinity increases!!

Thanks!

jsclownfish · Post by **jsclownfish** » Wed Sep 19, 2012 10:39 am

I like the idea conceptually, but wouldn't it be more difficult to control in a sump based aquarium set-up. In most systems the water level in the main stays steady and the evaporation shows up as a decrease in the water level of the sump. However, with a salinity change (increase due to evaporation) it would have to fill over a long period of time to adjust for the total volume of the system water coming to eqiulibrium again.

-Jon

Blawson · Post by **Blawson** » Sat Sep 22, 2012 4:27 pm

Think it's a pretty basic an straight forward ideal. Code just needs to say if salinity is less than 1.26 then turn on pump for 10 seconds. Wait an hour (or your preference and check again). You should be able to set the pump to turn off at 1.26. I would still use a float valve just in case.

dazza1304 · Post by **dazza1304** » Sun Sep 30, 2012 3:18 am

Just a quick update!

Have been using this for about 4 weeks now and works fantastic! Keeps salinity very stable!

Another benefit of this is that Ato is no longer sensitive to fluctuations in water level etc.

lnevo · Post by **lnevo** » Sun Sep 30, 2012 5:25 am

Lets see your code!

dazza1304 · Post by **dazza1304** » Sun Sep 30, 2012 7:54 am

Well, not mine, really its Robertos!! See below!

At the moment, I am using an existing tunze ATO that has a overfill float switch, so am just powering up the ATO from Port 5, and if overfull, the tunze float switch will stop pump from operating.

However, code is easily modified to incorporate a float switch for overfull cut out!

Basically, I have set that if salinity sits at 35.1 or above for 120 secs port 5 is switched on and ATO operates.

////// Place global variable code below here
unsigned long lastLowSal=now();

////// Place global variable code above here

////// Place your custom code below here
if (ReefAngel.Params.Salinity<351) lastLowSal=now();
ReefAngel.Relay.Set(Port5,(now()-lastLowSal>120));

////// Place your custom code above here

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