Brightwell Aquatics pH+ Liquid pH-Increaser for all Marine Aquaria 250mL / 8.5oz

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Brightwell Aquatics

Increases pH in all Marine and Freshwater Aquaria


  • Increases pH in marine and reef aquaria.
  • May be used to help increase pH in aquaria that have adequate alkalinity yet have chronically-depressed pH levels; while not intended to act as a permanent solution to such issues, pH+ may be used as neededuntil the cause of depressed pH is discovered and remedied.
  • Stronger than most competing products.
  • Composed of purified water and ultra-high purity materials.
  • Formulated by a marine scientist.
Technical Background
pH is a measurement of the acidity of a solution, such as aquarium water. The pH of natural seawater ranges from approximately 8.2 - 8.4, however maintaining pH in the range of 8.1 - 8.5 on a daily basis has no negative impact on captive marine organisms. To maintain stable pH within the desired range, the alkalinity should be maintained within a range of 7 - 12 dKH (2.5 - 4.3 meq/L). Aquaria with low circulation at the water’s surface, in which a CO2-injected calcium reactor is being employed, or in which a carbonate-deficient sea salt blend has been used, often have depressed pH. pH+ will bring pH in the aquarium back into the desired range. Use as directed and do not exceed a pH value of 8.5, as this pH may be stressful and/or fatal to sensitive aquarium inhabitants. Additionally, changes to pH should be made very gradually, again to avoid stressing aquarium inhabitants. It is not unusual for pH to fluctuate throughout the course of 24-hours between seemingly wide-ranging values (i.e. 8.1 at night to 8.4 during the middle of the day); this is a natural occurrence that is caused by changes in the rates of photosynthesis between dark and light periods. This situation is frequently encountered in aquaria with considerable growth of macroalgae (in the display aquarium or in a refugium). One proven method of minimizing this daily pH-fluctuation is to implement a refugium that is illuminated on an opposite schedule to the lighting for the display aquarium (known as reverse-daylight photosynthesis). In this method, the refugium is illuminated at night when the display aquarium lights are turned off, and vice versa; a 1-hour overlap of having all lights on encourages a smooth transition and little change in pH. The result is that photosynthesis takes place 24-hours a day and keeps pH as stable as can be managed. If pH levels are seen to be constantly below the desired level and alkalinity is within the proper range, increasing the circulation of water near the aquarium surface will often produce positive results; this practice increases the rate of gas exchange and encourages entrained CO2 to exit the aquarium before it has a chance to form the weak acids responsible for low pH and depletion of alkalinity.

Instructions and Guidelines
pH is always lowest a few hours after the main lights have turned off for the evening, and is highest a few hours after lights have been burning during the day. Adjust pH to remain with a range of 8.1 - 8.5 at all times. Before adjusting pH, ensure that the alkalinity in the aquarium is within a range of 7 - 12 dKH (2.5 - 4.3 meq/L). Determine the pH in the aquarium using an accurate test kit or recently-calibrated pH meter before using Brightwell Aquatics pH+. If the alkalinity is below the desired level, adjust this first and then allow 24-hours to elapse before re-testing pH, then add pH+ as directed below. [Alkalinity may be increased by using a buffer-type product according to the directions; again, an accurate test kit (for measuring alkalinity) should be used whenever bringing about a significant change to the alkalinity. Brightwell Aquatics’ Alkalin8.3 and Alkalin8.3-P (powder) are two buffer-type products that may be used for this purpose.]
Add this product at the maximum dosage of 5 ml per 20 US-gallons per 24-hours at the same time each day. pH will generally stabilize within 2 hours following product use, however livestock should not be subjected to a change in pH of more than 0.2 per 24-hour period, so do not overdose pH+. Repeat as needed to attain desired pH value. It is recommended that pH be maintained within a range of +/-0.2 at all times.

Caution: Contains carbonate salts; harmful if swallowed. If swallowed: give water, get medical attention. May cause eye or skin irritation. If in eyes, flush with water for 15 minutes, get medical attention. If on skin, wash thoroughly with water. Keep out of reach of children. Not for human consumption.

Guaranteed Analysis
Carbonate (min) 1,497mg/oz. (50,633 ppm)
Purified water, inorganic Carbonate salts

Manufacturer Info

Brightwell Aquatics Aquarium Supplies
The goal of Brightwell Aquatics is to provide the absolute highest quality, scientifically-sound products and customer service of any aquarium water care manufacturer, and to do it all in a straight-forward and honorable fashion. All Brightwell products are formulated by marine scientists with a passion for the aquarium hobby. They utilize the highest purity ingredients in concentrations that provide the most use to hobbyists. Nearly all Brightwell Aquatics products are over 99.9% pure. The usage guidelines of Brightwell Aquatics products are written in plain language but the company is always available to answer consumer questions. All products are lot numbered for quality control and customer service.



Experience Level: Intermediate

Brightwell Aquatics

This product works best with a drip method. No complaints,love it.

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Experience Level: Expert

Good product

I have found this product to be safe to use and effective when used in accordance with the instructions. Raises pH a little bit at a time, not a huge jump that might stress the fish.

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Dennis from CO


Experience Level: Intermediate

Great PH Product

Does just as it says. The tank or test waters I use start having a lower PH. A couple capfuls of the product raise it. Just test after each dosing and then add more if needed.

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Dan from California


Experience Level: Intermediate

No remedy for cronicaly low ph

I have chronically low ph in my 75 gallon tank. I tried everything including this product. The product works as described, if I add 2 squirts of this then my ph increases from 8.05 to 8.20, but then after a few hours it is back to about 8.12. So I would have to add this twice a day to keep the ph in the desired range of 8.1 - 8.4. The description says that it is not intended as a continuous solution, just as a temporary fix until the source of the chronically low ph is found (good luck with that). The only way I found to keep the PH in the desired range is continuous dripping of Kalkwasser. I combined a kalkwasser stirrer with the Tunze top-off system which seem to work ok, although I don't seem to have enough evaporation in my tank. I can then use PH+ to suplement the PH if needed.

1 out of 1 found this review helpful

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Experience Level: Intermediate

pH+ Increaser

I was looking for a solution where I could raise the pH in my tank without raising the alkalinity. My alkalinty would always be high, so I needed a product to just raise my pH. This product does it! Since, the addition my pH remains around 8.3-8.4. It hardly fluctuates and it never raises my alkalinity, just the pH. I highly recommend this product.

5 out of 5 found this review helpful

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