AquaMaxx Liquid Ph/Alkalinity Supplement - 16OZ

Free, Fast, and Flexible Shipping Options

• $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.

• 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!

Learn More About Shipping

60-Day Return Period with Easy Online Returns

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.

Learn More About Returns

Earn 5% Cash Back for Most Purchases

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.

Learn More About Rewards