Phosphate
From RTAW Reefpedia
| Water Parameter | |
| Phosphate | |
| Unit(s): | ppm |
| Target: | 0 ppm |
| Danger: | > 0.5 ppm |
| Tendancy: | - |
| Increased: | Food |
| Decreased: | Algae |
| Testing: | Rarely |
| Maintenence: | Water changes |
Contents |
Introduction
Phosphate is an important compound that is a key component used in all living things. However, due to the fact that it can be a limiting nutrient for algae and it can inhibit calcification, it is best to keep it to a level as low as possible.
Sources
There are three important sources of phosphate that can introduce it into a system.
Food
All food contains some phosphate in it, since it is an important component of all living things. When using a frozen product thaw out and rinse the water from the food, this will help to remove excess phosphate in the frozen water.
Top Up Water
Water used to replace the water lost by evaporation can end up being a significant source as it is added to the system constantly. That is why it is not recommended to use raw tap water, it should be filtered by either RO or DI before use.
Water Changes
When performing a water change, the new water can include phosphate.
Control
Methods that can be used to control the amount of phosphate within a system are:
Precipitation
Precipitation of calcium phosphate is favoured at high pH, such as present in the regions where kalkwasser is dosed.
Uptake
Living organisms required phosphate, so anything that is growing will use up phosphate. Favoured method here is to either use micro algae (such as in an algae turf scrubber) or macro algae then regularly harvest the algae.
Protein Skimming
A protein skimmer removes organic material and living organisms from the system, thereby exporting phosphate.
Binding
Some materials can actively bind phosphate to them, such as aluminium oxide and ferric oxide / ferric hydroxide.
Resources
- Phosphorus: Algae’s Best Friend by Randy Holmes-Farley - Advanced Aquarist's Online Magazine
- Phosphate and the Reef Aquarium by Randy Holmes-Farley - reefkeeping.com
- Vodka Dosing ... Distilled!: A Powerful Method for the Reduction of Nitrates and Phosphates within the Reef Aquaria by Nathaniel Walton and Matt Bjornson - reefkeeping.com
