Marine Depot offers FREE economy shipping for most products when you spend $29 or more! Your order will be delivered in up to 7 business days after it ships out. Economy shipping methods include UPS Ground, USPS First Class, and/or SurePost. You can also upgrade your shipping to Faster Shipping which speeds delivery to 1-5 days. A shipping upgrade is $2.99 for orders under 20 lbs, $3.99 for orders 21-40 lbs, and $4.99 for orders over 41 lbs. 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.
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.
API Stress Zyme is a biological filter additive containing live bacteria that improves the development of the biological filter and helps clean a dirty aquarium. The build-up of organic pollution in the aquarium inhibits the growth of nitrifying bacteria. The bacteria in Stress-Zyme keep conditions in the aquarium right for the development of the biological filter by consuming harmful organic pollutants. This speeds the development of the biological filter in newly set up aquariums. A build-up of organic compounds also promotes the growth of disease-causing organisms in the aquarium. Stress Zyme keeps the biological filter working properly by keeping the aquarium gravel and filter clean. Water quality and living conditions are improved when Stress Zyme is used on a regular basis.
Each teaspoonful of Stress Zyme contains 300 million bacteria. These bacteria are in a dormant state and become active when added to the aquarium. Stress Zyme has a five year shelf life and does not require refrigeration. Stress Zyme is effective in freshwater and marine aquariums.
Features:
Contains over 300 million live bacteria per teaspoonful
Breaks down organic compounds that cause dangerous conditions such as ammonia and nitrite poisoning and low oxygen levels
Helps to reduce sludge, keep your aquarium clean, and improve the natural aquarium cycle
Acts as a biological filter to ensure healthier fish and good water quality
For use in both freshwater and saltwater systems
No refrigeration necessary
Directions:
Shake well before using
For regular maintenance: Add 1 tsp. per 10 gallons of water weekly
For new aquariums: On the 1st, 7th, and 14th days add 2 teaspoonfuls (10 ml) for every 10 US gallons (40 L) of aquarium water. Thereafter, each week add 1 teaspoonful (5 ml) for every 10 gallons (40 L) of aquarium water
Compatibility:
Stress Zyme can be used with freshwater tropical fish, marine fish, invertebrates and coldwater species including koi and goldfish. Stress Zyme will not harm aquatic plants. Keep from freezing. Do not store above 120°F (49°C). Stress Zyme is completely harmless to humans and pets.
Aquarium Pharmaceuticals Aquarium Supplies Aquarium Pharmaceuticals (API) has been helping people take good care of ornamental fish for over 40 years. Their research and development scientists have advanced the care of fish with all-natural medications, stable bacteria for biological filtration, one-bottle test kits, consumer-friendly dosing caps and much more. They’ve received over 25 global patents for their breakthrough innovations in the aquatics industry. And they continue to look for ways to improve the fishkeeping experience for hobbyists. Research. Experience. Dedication to scientific, quality treatment for healthy fish. It’s what makes API the first choice of aquarium owners. API manufactures and sells hundreds of products across many different product categories, including aquarium and pond treatments, aquarium equipment, aquariums and fish nutrition.
Ask a Question Earn 15 Points when you answer a question
if you never tried this, you don't know what you are missing !!! for first time users i recommend if you buy the regular bottle, do a 4 day dosage.(for larger tanks 60gal+) smaller tanks should use a smaller amount). i have never overdosed with this product and i don't believe it is possible.(result...Read More
if you never tried this, you don't know what you are missing !!! for first time users i recommend if you buy the regular bottle, do a 4 day dosage.(for larger tanks 60gal+) smaller tanks should use a smaller amount). i have never overdosed with this product and i don't believe it is possible.(results may vary)4 day methodfirst day, use 1 quarter of the bottle or close to it if you feel uncomfortable.second day, do the same as first3rd day, do the same as first 4day, do the same as firston the fifth day test tank levels.if fish look stressed or not normal either stop or reduce daily dosageafter a week go back to the bottles recommended dosage results better/softer/ cleaner sand bedstabilized tank balance/reduced toxic levelsa tun of beneficial bacteriafish so happy they would kiss ya!this info was relayed to me be a 35 year vet in breading/selling of fish of all typesi never had a negative affect with this product no matter how much i dump in my tankbe smart and base what you do around the info i gave you and based on my tank size 60 gal if you have a bigger tank , you may use same dosage or may require more. i wouldn't use more than i described. also based on the 16oz bottlei used this method to quickly reduce a nitrate spike that occurred with i was moving live rocks off a sand bed. shaking the rocks clean while they were still submerged was a bad ideaHide
I've always been extremely happy with this product, it was wonderful to find it in larger sizes than the smaller bottles normally found in pet stores. Rock On!
I have a 30 gal reef with lighting and inhabitants for shallow reef, not to fast current flow, not much turbidity. I find this Sress -Zyme to be quite a step Up on helping to reduce to accumulation of dentritus the crabs and Wrasse's dont get. The water clarity and overall cleanliness within the tan...Read More
I have a 30 gal reef with lighting and inhabitants for shallow reef, not to fast current flow, not much turbidity. I find this Sress -Zyme to be quite a step Up on helping to reduce to accumulation of dentritus the crabs and Wrasse's dont get. The water clarity and overall cleanliness within the tank has taken a huge step in the right direction, too since I started using this as per advice from my LFS guy about 2 monthes ago.
Ill keep using it for sure.Hide
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.
Rack up reward points to earn discounts on future purchases! You can earn reward points by creating an account, writing reviews, referring friends, subscribing to our newsletter, buying products, and more!
Earn 5 reward points for every $1 you spend to get 5% cash back Most Products
Earn 1 reward point for every $1 you spend to get 1% cash back Abyzz, American Marine, AquaIllumination, AutoAqua, CoralVue, Digital Aquatics, EcoTech Marine, Giesemann, GHL, Hanna Instruments, Hydor, IceCap, Innovative Marine, Iwaki, Kamoer, Kessil, Klir, Korallen-Zucht, Maxspect, Mur-lok, Nano Box, Neptune Systems, NYOS, Oceanbox Designs, Pax Bellum, Radium, Red Sea, Reef Glass, Reef Octopus, Seneye, Somatic, Tunze, Vertex Aquaristik, and Waterbox Aquariums
You can also get bonus reward points by purchasing select items during special sales and promotions.
46,020 Reviews. 5,153,553 Products Shipped. #1 Aquarium Supply Store Online.
If you find a product we sell for a lower price at another online store, we will match their price to ensure you always pay the lowest amount when you shop with us.
Enter the price, shipping cost and website address where you found the lower price. Then click the "Add to Cart" button. We will review the lower price while processing your order and make any necessary reductions before your order ships. Some restrictions apply. See Terms & Conditions
