Stray Voltage/Inaccurate PH reading

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jayclaire
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Joined: Tue Jan 29, 2013 11:15 am

Stray Voltage/Inaccurate PH reading

Post by jayclaire »

How can I find and fix the stray voltage in my tank? I've relocated the PH probe several times (sump and DT) but the PH reading is still incorrect.

PH reading is accurate if the PH probe is inside a cup with my tank water.
Sebyte

Re: Stray Voltage/Inaccurate PH reading

Post by Sebyte »

The main cause of stray voltage seems to be from the float switches. First clean the leads and remake the joints to the cable. I have found that if you take a small piece if airline say 1" long and thread it onto the lead. Then make a soldered joint for the connection. Next cover the joint in silicon sealer, and slide the tube up to cover the joint. Try and pack the ends of the tube with sealer if you can. This is messy but I have found it better than using waterproof crimps.

Another cause for leakage could be any electrical powered device sitting in the water, such as pumps and heaters. Disconnect each device in turn and see if the fault goes away.

You can also add a titanium earthing lead to the tank, these are available at most LFS.

From a safety aspect always use a GFI outlet for your power supply.

Hope this helps.

BTW I eventualy replaced the ATO float switches with the water level modual.
jayclaire
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Joined: Tue Jan 29, 2013 11:15 am

Re: Stray Voltage/Inaccurate PH reading

Post by jayclaire »

Thanks for Sharing Steve...
I found out that my very old Tunze 6100 was leaking. My PH reading has been accurate since I've removed it.
thekameleon
Posts: 137
Joined: Sat Feb 16, 2013 7:44 am

Re: Stray Voltage/Inaccurate PH reading

Post by thekameleon »

Just starting experiencing the same thing today... Both float switches died after I moved them... One just wouldn't switch and now the other is showing stray voltage... Anyone know of any high quality float switches?
Piper
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Location: Oakley, CA

Re: Stray Voltage/Inaccurate PH reading

Post by Piper »

I was looking at this one from Amazon but I'm not sure if it's any better. I was also thinking about various standard and deluxe floats from BRS. I like their Deluxe Madison Horizontal float but I'd probably go with a RA Water Level Expansion before I put more holes in my sump. Unfortunately I have no experience with any of those floats.

I'm still using gravity fed ATO and using the floats to e-mail me when my ATO vat gets low and/or my sump level gets too low.

~Charlie
Sebyte

Re: Stray Voltage/Inaccurate PH reading

Post by Sebyte »

Go with the water level expansion. It is by far the most accurate and no chance of stray voltages,
thekameleon
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Re: Stray Voltage/Inaccurate PH reading

Post by thekameleon »

My only concern with that is the potential for loosing the seal with the Water Level Expansion. I also notice at times the WL varies 4 or 5 % at times. I'll look into it though.
thekameleon
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Joined: Sat Feb 16, 2013 7:44 am

Re: Stray Voltage/Inaccurate PH reading

Post by thekameleon »

OK so I reprogrammed to use the WL... Now what can I do with the two ATO ports? They will be empty and are begging to do something. One idea, I had is for water alarms... Any others?
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lnevo
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Stray Voltage/Inaccurate PH reading

Post by lnevo »

I dual use one for alarm and automated water changing and I'll be using the other as a skimmer shutoff connect to an avast marine skimmate collector.
rimai
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Re: Stray Voltage/Inaccurate PH reading

Post by rimai »

I use for skimmate container alarm
Roberto.
thekameleon
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Re: Stray Voltage/Inaccurate PH reading

Post by thekameleon »

I have thought about a skimmate alarm/pump or auto water changing, but it appears the ATO capabilities are all wired to one ATOExtendedTimer... Now if we had separate timers for WL ATO, SingleATOHigh and SingleATOLow. Then we can effectively have 3 independent ATO/drainers... Hint hint... nudge nudge
rimai
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Re: Stray Voltage/Inaccurate PH reading

Post by rimai »

We had them separate in the past and it was a nightmare to deal with all of the different ones.
Everyone was getting confused about which value to change, so I decided to combine every ATO timeout into a single location to make things easier.
But if you are doing something other than ATO, you really don't want to use timeout anyway, right?
Roberto.
thekameleon
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Re: Stray Voltage/Inaccurate PH reading

Post by thekameleon »

Here are the scenarios I am thinking:

A skimmate toilet of sorts now before you laugh here me out. Once the skimmate gets to a certain or at a specified interval a electric water valve (similar to the ones used in washing machines, opens up and water is then pushed into the holding tank. Now the holding tank has a drain line that goes into the sewage system. (I was thinking the point of where washer house goes into). I could use a standard toilet valve to control the fill. Now I would need a timer to engage to turn off the valve once it is triggered.

I would also love to completely automate my water change. So auto fill my 55G water container... auto mix in salt in and stir it up for 6 hours, initiate water change mode on the reef angel, drain the sump (it hold 55g of water), then fill it from the water barrel, turn off water change mode on the reef angel... Presto... automated water change.
rimai
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Re: Stray Voltage/Inaccurate PH reading

Post by rimai »

Interesting...
I'm sure doable!! :)
Roberto.
thekameleon
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Re: Stray Voltage/Inaccurate PH reading

Post by thekameleon »

Ahh I forgot to mention in the water container, I would have a temperature probe as well, with a heater for the container. This way I can match the temperatures. I am not so worried about exact salinity matching as I would have a fixed about of salt prepared ahead of time for mixing. Now the biggest challenge is how to I had the salt automatically. My first thought, would be to pump water into the salt holding chamber and let it naturally just dissolve into the flowing water. I wonder though if the salt would eventually clump up or block the water flow... This is going to be my home depot project for sure :)
rimai
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Re: Stray Voltage/Inaccurate PH reading

Post by rimai »

You definitely don't want to do that.
Parameters will be all messed up.
You will have supersaturation which will cause the calcium to precipitate and you will loose a lot in the precipitation.
I'm no chemist, but once it precipitates, it's hard to bring it back. That's the theory of the calcium reactor. You drop ph so low that it starts dissolving calcium back into the water.
Roberto.
thekameleon
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Re: Stray Voltage/Inaccurate PH reading

Post by thekameleon »

OK so I am up for creative ideas for automating the addition salt to RO water.
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lnevo
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Stray Voltage/Inaccurate PH reading

Post by lnevo »

I would automate a gradual continuos change and just mix up a batch every week. Set your ato relay based on salinity.
thekameleon
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Re: Stray Voltage/Inaccurate PH reading

Post by thekameleon »

Its the mixing part I want to automate. I know that 38 grams of salt can be dissolved into 100 grams of water... Is there a risk in mixing a concentrate salt water and then mixing that?
rimai
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Re: Stray Voltage/Inaccurate PH reading

Post by rimai »

If it were just salt, it would not be a problem.
The problem is that we use a salt mix, which included some other chemicals that when super saturated, react differently.
The soluble Ca for one is going to become a precipitate and your water will be cloudy and you will loose lots of the Ca in the process. I'm no chemist, so I don't know the exact reaction that happens, but I do know that it does.
With the loss of Ca, you will need to supplement with dosing later on. It's just a waste of the good salt mix... lol
I wish there was a good method of doing this too, but the only thing I can think of is mechanical shaker :(
Roberto.
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