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Free Upgraded Shipping For Orders $250+
Most orders over $250 qualify for FREE upgraded shipping! Your order will be delivered 1-5 days after it ships out. Thanks to Marine Depot's two strategically located warehouses in Nevada and Georgia, over 90% of shoppers receive their orders within 1-2 business using this level of service. Orders placed before 10:30 am PST Monday-Friday are shipped the same day. Free shipping is only available within the contiguous United States. Frozen foods, live foods, and items shipped directly from the manufacturer do not qualify for this special offer.
$2.99 Flat Rate Shipping For Orders Under $29
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 up to 7 business days after it ships out. Orders placed before 10:30 am PST Monday-Friday are shipped the same day. Our $2.99 flat rate shipping is only available within the contiguous United States. Frozen foods, live foods, and items shipped directly from the manufacturer do not qualify for $2.99 flat rate shipping.
Frozen foods are delivered 1-3 business days from the day your order ships. Frozen foods are shipped every Monday and Tuesday. Shipping cut-off is Tuesday at 10 am PST (1 pm EST). Orders received after 10 am PST on Tuesday will be shipped the following week. Shipping and handling is a $19.99 flat-rate charge so you can order as much or as little as you like.
Orders not shipped within the contiguous United States—the 48 U.S. states on the North American continent south of Canada plus the District of Columbia—are considered international orders. International orders are not eligible for Marine Depot’s free shipping promotions and additional surcharges may apply. It is important to note that not all products we carry can be shipped internationally. Any brokerage fees, tariffs and/or taxes will be billed to you directly by the shipping courier. International customers must use the same billing and shipping address.
High quality and economical hang-on overflow box allows you to easily add a sump, refugium or wet/dry filter to your system. U-tube design allows for easy and convenient installation. Adjustable pre-filter hight allows you to adjust the water level inside your aquarium.
Includes
1" Bulkhead
U-tube
Noise-Reducing Cylinder Foam Sleeve
Nylon screw and wing nut
Surface Skimmer Box
Specifications
Model
Tank Size
Max. Rim Size
Overflow Body Dimensions
Surface Skimmer Dimensions
Max. Flow Rate
Drain Size
Nano
up to 30 Gal
1.5"
4"x2.5"x8"
4"x1.5"x6"
200GPH
3/4"
OF-300
up to 60 Gal
1.5"
6"x3"x10"
6"x2.5"x6"
300GPH
1"
OF-800
up to 120 Gal
1.5"
8"x3"x10"
8"x2.5"x6"
800GPH
1"
OF-1000
up to 150 Gal
1.5"
9"x3"x10"
9"x2.5"x6"
900GPH
2 x 1"
OF-1200
up to 200 Gal
1.5"
10"x3"x10"
10"x2.5"x6"
1000GPH
2 x 1"
OF-1800
up to 320 Gal
1.5"
12"x4"x10"
12"x2.5"x6"
1600GPH
1-1/2"
Manufacturer Info
Marine Depot was started in 1998 by a self-professed reef geek and pre-med student Ken Wong. Ken envisioned a one-stop shop where customers could find everything they needed, from technical product specifications, reef aquarium information, expert advice on the hobby and friendly one-on-one customer support. Having grown from a one-man crew to being one of the world’s largest suppliers of reef and marine aquarium products, this very core philosophy still lives strong in the Marine Depot culture 20 years later.
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Q
Marine Depot Overflow Box OF-300 Can this be used in the Uk ( UK PLUG )
CONS
Needs slight modification for quieter operation
REVIEW
I purchased this to replace an overflow I've had going for over 20 years that was pretty old and worn. This new one is well-constructed, and I especially liked the slim profile that allowed me to move it behind the tank without needing to push the tank and stand too far off the wall. It was easy eno...Read More
I purchased this to replace an overflow I've had going for over 20 years that was pretty old and worn. This new one is well-constructed, and I especially liked the slim profile that allowed me to move it behind the tank without needing to push the tank and stand too far off the wall. It was easy enough to install and start up, especially if you've used siphon overflows before. I did find it to be pretty noisy, with a lot of gurgling and "whooshing" as the air going down the drain with the water was not maintaining a consistent flow down the drain pipe to the sump. Part of this was due to the fact that my return pump pushes about 350 gph back to the tank, which was causing the overflow to fill up above both the standpipe and the small plastic tube glued to the inside of the standpipe, negating the ability of the plastic tube to maintain steady airflow with the draining water. I reduced the return flow with a valve, which reduced the noise somewhat, but I found the overflow still had the occasional gurgle and slurping sounds. However, after a couple days I came up with a simple mod that silenced the drain pipe noise completely. I cut a 6" piece of airline tubing, and inserted it halfway down the small plastic tube. That provided a clear path for air to be carried down the drain with the water, ending all of the odd drain sounds. I used a small airline clip (sans suction cup) around the airline tube just above the top of the small plastic tube to hold the airline at my desired level. The sponge still slides down around the standpipe as designed, and now the only noise the overflow makes is the occasional light trickle from the skimmer box inside the tank. Operation has been perfect so far. I turn off the return pump two times each day for feeding, and have not had a siphon loss at any time.Hide
PROS
good alternative to taking your tank down to drill it
CONS
uses the syphon tube
REVIEW
This is a well made product. Personally, I used mine for six months or so and now it is up for sale. I just don't trust syphon tubes. It does work well with the high level sensor which will shut off your return pump.
I ordered the OF-300 and the package arrived on time, except what was inside wasn't my order. MD fixed the mix up and rushed my order to me, that also arrived on time. When I opened the box, the foam sleeve was missing and the silencer tubes were in two separate pieces. Maybe it's not a big issue, b...Read More
I ordered the OF-300 and the package arrived on time, except what was inside wasn't my order. MD fixed the mix up and rushed my order to me, that also arrived on time. When I opened the box, the foam sleeve was missing and the silencer tubes were in two separate pieces. Maybe it's not a big issue, but it seemed that the box was thrown together haphazardly. After the first order being messed up, I would have expected a bit more care. The product, otherwise, seems well built.Hide
PROS
Pretty silent, Easy setup, Dont have to drill tank
CONS
No instructions, leaky bulkhead that needs silicone
REVIEW
This overflow is pretty dang good. Its easy to set up and its mostly silent. There are a few small issues though. It doesnt come with directions so youll need to look them up on Youtube. The bulkhead leaks not matter how tight. I had to silicone it. Other than that, I love it.
I run one of these box's on my 55g corner tank and it works great! It is very quiet, doesn't leak, and is very durable. It's slim design and foam sleeve make it able to be put anywhere. Would recommend it to anyone.
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 up to 7 business days after it ships out.
free shipping for orders $29+
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 $29 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 $2.99—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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