The Original MJ multi-use submersible pump and power head is built to perform and last under the harshest conditions. Ideal for wave makers, protein skimmers, calcium reactors, nano aquariums, under gravel filters and hydroponic applications.
|Model||Watt (120v-60Hz)||Max Flow (gph/lph)||Max Height (in / m)|
|MJ400||5||106 (400)||29" (.73m)|
|MJ600||7.5||160 (600)||53" (1.35m)|
|MJ900||8.5||230 (870)||46" (1.17m)|
|MJ1200||20||295 (1100)||69" (1.74m)|
SPECIAL NOTE for REACTOR users: The MJ pump is the perfect pump for use with reactors on reef aquariums. One thing to understand is that reef aquariums have high levels of calcium, in fact at almost saturation levels, and areas with slightly higher temperatures can have active and dramatic precipitation of calcium on parts, ie impellers and impeller shafts. In as little as 4-5 months, calcium can build up enough to stop an MJ pump. Calcium build up is NOT covered by the warranty, but is easily kept in check with routine maintenance. Every 2-3 months, take out the MJ and remove the impeller, soak in distilled vinegar for 15-20 mins, then scrub parts with an old toothbrush and work the impeller up and down shaft to break up and mineral deposits. Rinse with fresh water and re-install impeller and MJ into system. This simple maintenance will keep your MJ running like new for years.
Cobalt Aquatics was established in April of 2011 by a leadership team with over 60 years of combined Aquatic Industry experience. The three hardcore fishgeeks; Les Wilson, a former research biologist and director of marketing for United Pet Group Aquatics, Viral Surati, a pioneering high end African cichlid importer, TFH magazine and United Pet Group key accounts manager, and Randy Parham, a founding member of the Marineland Aquarium Products sales team and national sales manager for United Pet Group Aquatics got together to form the company.
From those simple beginnings in 2011, Cobalt Aquatics now features a product mix of hundreds of items from flake food to frozen mysis shrimp, to the original MJ pumps, to award winning heaters and the innovative Egg Rockers.
With a worldwide supply chain including products and supplies from the USA, Italy, Poland, The Netherlands, South Korea and others, Cobalt has grown and now occupies a 20,000 square foot facility, and employs 10 warehouse and office staff, and 4 full time and 3 part time field and telesales sales reps and territory managers.
Most orders under $29 ship for only $2.99 using a mix of economy shipping methods including UPS Ground, USPS First Class, and/or SurePost. Your order will be delivered in 1-7 business days after it ships out.
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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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.
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.
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.
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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