The pH value represents the acidity (alkalinity) of water. The pH value is a measure for the acid or alkaline character of an aqueous solution.
A pH measurement is one of the most important measurements in an aquarium. It is extremely important to compare the measured pH value to other measurements of previous days, always taken at the same time, since the pH value varies greatly during the course of the day (e.g. from illumination).
The pH value inside the aquarium should be kept as constant as possible. One option to do so, is to stabilize KH in the range of 7-10°dH. The alkalinity (KH) buffers the pH value and thereby avoids pronounced pH fluctuations.
A pH value between 8.2 and 8.4 is considered optimal for a salt water aquarium. The GIESEMANN pH test was specifically developed for this pH range in salt water aquariums.
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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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