New Tunze Osmolator 3155 Issues

Banjo

New member
Recently purchased a Tunze 3155 and set it up in the rear chamber of my Red Sea Max E170. I put the very tip of the optical sensor to where I want the water level to be, in the return pump chamber so it is perfectly still. I am not sure how far the water level is supposed to rise over the optical sensor once it kicks on, but it's constantly raising the level to the point it's trigger the float switch and sounding the alarm. It's super frustrating as I then have to take out some water and let it reset. It may work once or twice to the proper level and stop, but then starts up several minutes later and overfills (til' the point of sounding the alarm) even though the aquarium doesn't need to be filled.

Over the last several days, I have just turned the unit off as I've been too busy to deal with it. I had a free day today and started researching the issue and some people said to wash the sensor in hot, soapy water. I washed it for a minute or two, cleaned it off, and put it back in the proper position. It worked the first time it ran and now it just overfilled AGAIN.

Is this a defective optical sensor, controller, or what's going on? I never had a single issue with my JBJ ATO, but I've heard the Tunze is much better and I wanted something that had both optical and mechanical switches for safety since I just moved into a new house. It has been nothing but frustrating since I've received it several days ago and I'm at the point where it needs to start working or I'm just going to return it and stick with my JBJ.

I have reduced the flow on the unit/pump to the minimum "nano" setting and have the top off tubing positioned about 5" away from the sensor unit. Not sure what else to do.

Thanks for the help.
 
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Just tried putting the top off tubing in the skimmer chamber, which is on the opposite side of the rear sump, still having the same issue.
 
Take a look at issues 2 and 3 in this list,

1) A siphon, if it is a siphon the issue will be seemingly random, it will tend to only occur when the reservoir is full and the water will fill to a level possibly above or just below the float. Siphon situation 3 is the most probable cause but note as shown in 4 that a loop will not solve it, the end of the hose must always terminate above the reservoir water level.

Siphon-Situations-688x459.png

2) A sensor issue. The first test is to use the self diagnostic test on the Osmolator to verify the sensor is in working order.

1) With the sensor completely wiped dry, plug in the controller. The sensor MUST be clean and dry for this test to work, a wet or dirty sensor will always fail.
2) All 4 lights will flash and it will beep, a single light will show for 1 seconds and then the normal 15-20 second pump run at startup will begin.
3) This light that is on one second is the optic sensor status, green means pass, yellow means it is marginal, red means it failed.

Assuming it passes the self test the issue is bubbles, optic sensors work by detecting the refraction of air vs water and make no differentiation between a bubble or being dry. The most overlooked source of bubbles is placing the top off hose in the vicinity of the sensors, the incoming splash will introduce bubbles and cause a fill. The hose can be routed to any area of the sump or main tank, and the optic sensor must be in a calm and bubble free area. A definitive test to verify bubbles are the cause is if you can catch it in the act of an overfill and wipe your finger across the sensor and filling stops within 5 seconds, the cause was bubbles.

3) There is a 3rd possibility but this is relatively obscure and only will apply to tanks under 50 gallons or due to a misunderstanding of how the Osmolator works. The Osmolator has timed functions in addition to sensor controlled functions and for the first 25-30 seconds it is not actually detecting water levels and is instead running a series of self diagnostic tests. The pump will always run for 15-20 seconds when you first power it up, this is so the installer can verify the pump is operational and the pump and tubing are primed and ready to fill. Also, the Osmolator always waits 5 seconds to fill to account for waves and surface movement and overfills for 5 seconds so the pump is cycled on less often. If the tank is under 50 gallons you need to open the controller and reduce the pump speed to “nano” and if it is under 30, an additional restriction such as a drip irrigation valve might be needed, this will reduce the amount of water added by these timed sequences to avoid raising the float.
 
Thank you for the reply.

I followed issue #2 and the single light shows green for 3 seconds or so and then the normal pump run turns on. I currently have the RODI tubing feeding back into the top off bucket so I can keep the aquarium water level and where it's supposed to be.

The initial pump run will turn off after 20 seconds or so and it will show the aquarium as the correct level on the controller. About five minutes pass by and the pump will turn on again and if I rub the optical sensor it will cease immediately. It will continually do this, every 5-10 minutes. I'm assuming this is a problem with microbubbles.

I have the sensor unit positioned in the return chamber on the rear sump of the RSM E170 where there is no water movement. I am unsure of where the microbubbles are coming from as the protein skimmer is on the other side of the rear sump, with a baffle in-between. I currently have the top off hose feeding back into the RODI bucket, so it isn't an issue there. Further, when it was in the aquarium, it was feeding into the protein skimmer's chamber. The optical sensor is in the calmest part of the tank. Could it still be an issue with the sensor being over-sensitive or something?
 
Try this, submerge the optic sensor and leave the controller unplugged until Saturday, this will give it time to get a biofilm. Plastic by its nature repels water and attracts air like a magnet, this is the same reason skimmers need to "break in". If there is no major source of bubbles this will very likely solve the problem.
 
Thank you for the suggestion. I’ll go ahead and try that out. The source of bubbles is definitely from the protein skimmer since it is a new setup, I can see the bubbles in the return chamber. Maybe I’ll try putting an additional sponge or something as well that will block some of them before the sensor. The issue with the Red Sea Max is there would be no other area for me to place the sensor as the rear sump loses water before the display area and the other side of the rear sump houses the protein skimmer.
 
If possible you might try slowing the return flow, this tends to make the biggest difference if a sponge trap is already in use.
 
Try this, submerge the optic sensor and leave the controller unplugged until Saturday, this will give it time to get a biofilm. Plastic by its nature repels water and attracts air like a magnet, this is the same reason skimmers need to "break in". If there is no major source of bubbles this will very likely solve the problem.

That seemed to do the trick. I had it submerged until Sunday and it has now worked flawlessly ever since. Thank you!
 
Hello hopefully you can help me . I am a newbie a just got the 170 e max. I purchased the Tunze3155 and was wondering if you could send post pics of your install? I see where talk about it is return chamber but dont see how it would fit with the big sponge filter in there. Any help would be greatly appreciated
 
Hello hopefully you can help me . I am a newbie a just got the 170 e max. I purchased the Tunze3155 and was wondering if you could send post pics of your install? I see where talk about it is return chamber but dont see how it would fit with the big sponge filter in there. Any help would be greatly appreciated
Did you ever get your Tunze3155 set up in your Max E170?. If so looking for some guidance on how and where. Thanks
 
Unfortunately I have no experience with this all in one tank, the sensors need to be in the return pump chamber and for a small tank, you need to open the controller and reduce the pump speed to nano, if this tank is under 25 gallons, you need to add a small valve to the end of the hose to further restrict the flow. Typically on systems under 35 gallons, the Nano Osmolator is a better option.
 
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