Read "The Sumpless ATO from XP Aqua is the First Auto Top-Off Built for Tanks Without Sumps" on the Marine Depot Blog, written by its creator, Joseph Chang.
Why Choose Sumpless ATO?
Sumpless ATO is the first and only ATO designed specifically for aquariums without sumps. The combination of the sleek overflow box and the innovative dual-optical sensor ATO will help to keep your aquarium topped off and your water crystal clear. The overflow box easily mounts to any aquarium with its magnetic mount. It acts as a surface skimmer to rid your aquarium of undesirable oily surface skim and doubles as a media reactor for carbon, GFO or any media of your choice. XPAqua’s proprietary dual-optical sensor packs two precise level sensors in one incredibly small package. In addition to keeping your water level constant, the two sensors also work in concert with the intelligent QST programming to help prevent overfilling. With so many features never seen before in ATO’s, the XPAqua Sumpless ATO is the ultimate ATO solution for aquariums without sumps.
*Please avoid setting up the sensor in an area with micro bubbles or direct light.
Ever since the ATO systems were invented by Tunze in 1985, they have been helping saltwater reef aquarium hobbyists maintain stable salinity levels and offering a ton of convenience. ATO is short for ‘aquarium top off’ system. It is also called an ATK ‘aquarium top-off kit’, or osmolator / osmo regulator in Europe. Here at XP Aqua, we have combined all the best ATO technologies and added several proprietary features to create the safest and most dependable ATO money can buy! Our micro sized ATO sensor features two precise optical sensors to offer you more protection. Additionally, each XP Aqua ATO system includes our intelligent QST programming to prevent overflows. If you are looking for the best ATO system, check out our awesome line of ATOs!
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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 1-7 business days. Just spend $29 or more!
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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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