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The TUNZE Osmolator 3155 is an automatic top off (ATO) system for marine and reef aquariums. The Osmolator – short for Osmotic Regulator – automatically adds freshwater to compensate for evaporation in your saltwater aquarium.
The high-tech German designed Osmolator uses a precision optical sensor to measure the water level. Water continuously evaporates from the aquarium, leaving the salts behind. This causes the salinity to increase. When you manually pour in water the salinity is suddenly decreased. This “salinity rollercoaster” stresses the fish and invertebrates by causing extreme fluctuations in osmotic pressure.
The Osmolator puts an end to this by continuously sensing the rate of evaporation (water level) and adding back the right amount of freshwater. This brings osmotic stability to the aquarium and keeps your sump and aquarium water at the right level.
Here’s what we really like about the Osmolator:
TUNZE invented the ATO and has been perfecting it for 30 years
Precision optical water sensor detects the slightest change in water level
Easy to install and adjust using the Magnetic Sensor Mount
Status lights display functions and sounds a warning in case of trouble
Built-in safety features prevent overfilling of the aquarium and shuts the system down
Comes ready to install – all you need is a reservoir or bucket
The Osmolator can be used on any aquarium, even freshwater tanks. It works when installed inside the aquarium on tanks without a sump. If you have a sump the sensor must be installed there since that is where the water level changes as it evaporates.
Features:
Complete kit with power supply, metering pump, hose and sensor mounting system.
The water level sensor has no moving parts to wear out and is not affected by suspended dirt, light or magnetic fields.
Optical sensor ignores gentle water movements caused by wave makers and circulation pumps.
An independent safety sensor with a separate power supply circuit and relay ensures reliable overflow protection.
A microprocessor monitors the water level in the reservoir and prevents the pump from running dry.
All functions are clearly displayed by colored LEDs and warning signals.
The Osmolator uses ultra-low voltage for complete safety.
Metering pump flow rate based on pumping height: 3 feet:13.7gph, 5 feet:12.4gph, 6.5 feet: 7gph, Maximum pumping height: 7.22 feet
Magnetic Mount System: Maximum glass thickness ½ inch
For indoor use only
2-year warranty
Manufacturer Info
Tunze For forty-five years the name TUNZE® has been synonymous with aquariums. Many products and components which we have developed in the course of time are now standard features of aquarium technology today. This confidence in TUNZE is no coincidence. The company has remained true to its philosophy right from the beginning, researching water biotopes all over the world to develop components which enable natural water conditions in the closed environment of an aquarium. In the implementation of know-how, effectiveness and efficiency, TUNZE® takes the lead in environmental compatibility. Their motto is: quality and reliability. These values are upheld with well thought-out and precise tool making by highly qualified experts. The brand names of TUNZE® and Turbelle® meet the expectations of the seal of quality; Made in Germany. Many of the products shown in this catalogue are protected by national and international patents.
Warranty
Manufacturer`s Warranty: 2 years from date of purchase.
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9 Questions
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Q
Would the Osmolator 3152 work on my 200 gallon aquarium? Looks like the same basic setup as the 3155 except for the optical sensor and Electroic controls.
First pump died after a couple of months. Replaced it and the new one died a month later. Tried replacing again but couldn't get the system to work. Contacted support and never heard back.
this is my first ato and i love not having to add water by hand. sometimes it seems to be adding more water than i think it should, but that may be because it's hard for me to place the sensor in the same place every time due to my return pump chamber being in the back of my sump. also it pumps wa...Read More
this is my first ato and i love not having to add water by hand. sometimes it seems to be adding more water than i think it should, but that may be because it's hard for me to place the sensor in the same place every time due to my return pump chamber being in the back of my sump. also it pumps water every time you power up, so i would not buy this for a nano. overall i am happy with it, i like the optical and mechanical backup sensor.Hide
Bought this based on previous buyers reviews and recommendation for a quality, reliable ato. Easy install and so far happy with this buy. Sure it will be a reliable ato for my first reef tank.
PROS
Comes with everything you need, easy to install
CONS
Poor instructions
REVIEW
Despite the instructions the 3155 is easy to install. Check out one of the YouTube videos for additional help. You need to shake the pump under water to get the air out on your initial fill of your storage container. Once installed the product works great. The pump is not as quiet as I would ha...Read More
Despite the instructions the 3155 is easy to install. Check out one of the YouTube videos for additional help. You need to shake the pump under water to get the air out on your initial fill of your storage container. Once installed the product works great. The pump is not as quiet as I would have liked. With normal household noises you will barely notice it. If your tank is in your bedroom and you are a lite sleeper I would put the 3155 on a timer so that it doesn’t come on while sleeping.Hide
I've had the tunze 3155 running for 2 weeks now on my rsr v350 and I am very happy with it. I am getting about 4 days out of the 7 gallon bucket reservoir. I had a couple of issues setting it up but resolved then after researching on line
Most orders under $39 ship for only $5.99 using a mix of economy shipping methods including UPS Ground, USPS First Class, and/or SurePost. Your order will be delivered in up to 7 business days after it ships out.
free shipping for orders $39+
We ship 99% of the products we carry for free within the contiguous United States using a mix of economy methods including USPS First Class Mail, SurePost and UPS Ground. Your order will arrive in up to 7 business days. Just spend $39 or more!
free faster shipping for orders $250+
Over 90% of shoppers receive their orders within 1-2 business days. Upgrade from free economy shipping to faster shipping for only $5.99—or spend $250 and we'll upgrade you automatically!
need your order even faster? no problem!
Expedited shipping services are available for most products if you are in a hurry. Get guaranteed delivery in 2 business days, 1 business day, or next day by 10:30 am. Costs vary by location.
buy it today and we'll ship it today
Same-day shipping is available Monday-Friday for most products—place your order by 10:30 am PST. Pre-ordered and back-ordered items do not qualify, nor do drop-shipped, live, or frozen shipments.
live plants, live foods, and frozen foods delivered to your door
We ship live plants, live foods, and frozen foods within the contiguous United States. Each of these categories is subject to its own $19.99 flat-rate shipping fee to cover the special packaging and/or expedited shipping costs required to ensure safe delivery. Orders with 12+ live plants ship free!
Return any new and unused item within 60 days for a full refund. Having difficulty with a product? Contact us to speak with an aquarium expert. If you need a replacement, fill out this form.
A small segment of the 180+ brands we carry require that customers contact them directly if/when problems arise. You can view the full list of those brands and get their contact info here.
We are unable to accept returns of Digital Aquatics, Neptune Systems, Vertex Aquaristik, Aqua Illumination (AI), EcoTech Marine, GHL, or Seneye products once the manufacturer's packaging seals have been broken.
Marine Depot is an authorized reseller for every product we carry. That means when you buy aquarium supplies from us, your products are not only backed by our own 60-day return policy, they also carry full factory warranties, where applicable. Some items have a 1-year warranty, others have limited lifetime warranties. Warranty coverage varies from manufacturer to manufacturer, so please read the product description of the item(s) you are considering thoroughly for details or contact us if you have warranty questions.
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