Marine Depot now offers FREE economy shipping with no minimum purchase for 99% of the products we carry! Orders under $299 are shipped FREE using a mix of economy shipping methods including USPS First Class Mail, SurePost and UPS Ground. These shipments are typically delivered in 5-7 business days. Orders placed Monday-Friday before 10:30 am PST are shipped the same day. This offer is valid for orders shipped within the contiguous U.S. only. Frozen foods, live foods, and items shipped directly from the manufacturer do not qualify for this special offer.
$4.99 Upgraded 1-5 Day Shipping (FREE for orders $299+)
This is the shipping method most Marine Depot customers are accustomed to and is really the sweet spot for service and value. Thanks to our two strategically placed warehouse locations, over 90% of Marine Depot shoppers receive their orders within 2 business using this level of service (UPS Ground).
UPS Ground shipping is available for only $4.99 but is FREE with orders over $299. This shipping upgrade speeds delivery time to 1-5 business days. This offer is valid for orders shipped within the contiguous U.S. only. Frozen foods, live foods, and items shipped directly from the manufacturer do not qualify for this special offer.
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.
Instant Ocean Hydrometer`s new improved design delivers precise full-range salinity and specific gravity readings - accurate to 0.001 - every time. Easy-fill convenience keeps hands dry when filling. It has a durable, permanent needle mount and easy-read 2-color scale with "safe zone" and an extra-wide stabilizer base. Ideal for use in water temperatures of 68 - 85°F.
Manufacturer Info
Instant Ocean Aquarium Supplies Instant Ocean is one of the aquarium industry`s most trusted brands of marine salt. Instant Ocean products are designed for aquarists who wish to re-create a thriving ocean habitat in their own home. Instant Ocean Sea Salt is one of the most popular brands on the market and is used by public aquariums, zoos and marine adventure parks throughout the country. Instant Ocean continually refines both the ingredients and the manufacturing process of their salt mix to make sure every necessary major and minor trace element is present in every single batch.
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All the "experts" tell you to get a refractometer. If used properly, a hydrometer is sufficiently accurate. Maybe not if running experiments for publication in a scientific journal. But just fine for reef tanks. Someone here described the bast way to use it without getting bubbles on t...Read More
All the "experts" tell you to get a refractometer. If used properly, a hydrometer is sufficiently accurate. Maybe not if running experiments for publication in a scientific journal. But just fine for reef tanks. Someone here described the bast way to use it without getting bubbles on the reading arm. Very good advice. Save yourself $50 and spend it on corals and/or fish.Hide
Reading is way off. I setup my new tank at 1.024 according to this product. After my tank cycled I brought my water to the lfs for them to check my param and salinity reads 1.029. Luckily no fish or coral!
I have been able to keep my livestock healthy for at least 10 years using this product. While not as accurate as a refractometer, it's very close. I have two of these and they test only about .002 higher than the refractometer. For the price and ease of use it's a great way to get started and kee...Read More
I have been able to keep my livestock healthy for at least 10 years using this product. While not as accurate as a refractometer, it's very close. I have two of these and they test only about .002 higher than the refractometer. For the price and ease of use it's a great way to get started and keep your hands dry. Clean up with tap water is a breeze. Also this item is very easy to read without glasses or bright lights. Some other reviews claim this item was reading way off in terms of accuracy. These can get clogged up with salt if water is left too long...Also this item requires a seasoning period for about 24 hours...You put salt water in there for a day before normal use...do this only when you first get it or after a harsh cleaning. Great productHide
I have used this type of hydrometer in the past and continue to use it as a cheap backup. These instruments are fairly accurate and good to have around. I always check against a refractometer to determine how close the hydrometer is. I have not seen one that has been right on and I have seen some...Read More
I have used this type of hydrometer in the past and continue to use it as a cheap backup. These instruments are fairly accurate and good to have around. I always check against a refractometer to determine how close the hydrometer is. I have not seen one that has been right on and I have seen some as far off as 1.005 from actual...that is enough to upset certain inverts and species sensative to salinity. Good product for what it is. Thanks MarineDepot for the great serviceHide
I got this because I was trying to get by cheaply to start my aquarium but after much review I have found that it would me much better to have a refractometer.
Mine worked great, I have a Digital refractometer as well and have tested it against the more accurate refractometer and was always dead on. The big complaint is you have to slowly fill it and then knock the bubbles off, and there is always a bubble or two that doesn't want to let go leaving me figh...Read More
Mine worked great, I have a Digital refractometer as well and have tested it against the more accurate refractometer and was always dead on. The big complaint is you have to slowly fill it and then knock the bubbles off, and there is always a bubble or two that doesn't want to let go leaving me fighting to get it off. If you can't afford a refractometer (I highly recommend the Milwaukee) I would highly recommend this product otherwise buy a digital and save yourself some time and probably money as you may end up buying one anyways. Otherwise this hydrometer gets the job done as long as you follow the directions.Hide
Most products ship free—no minimum purchase required
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 5-7 business days.
upgrade your shipping for only $4.99—free upgrade for orders $299+
Over 90% of our members receive their orders within 2 business using UPS Ground. Upgrade from free economy shipping to UPS Ground for only $4.99—or spend $299 and we’ll upgrade you automatically!
need your order even faster? no problem!
Expediated 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 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.
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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