- Sku: 185
- Vendor: Seachem
Seachem PhosGuard
Seachem PhosGuard rapidly removes phosphate and silicate from marine and freshwater aquariums, starving the nuisance algae that feed on them. Its spherical, highly porous beads pack a huge amount of surface area into a small volume and let water flow freely through and around the media, so it works fast and lasts. Browse the rest of our filter media and cartridges and the full Seachem lineup.
How It Works
Phosphate and silicate are the fuel for hair algae, diatoms, and green water. PhosGuard adsorbs both as water passes through it, pulling them out of the system so algae cannot use them. It works in fresh and salt water, though it is most efficient in marine tanks. Run it in a media bag or fluidized reactor with good flow, and replace it when phosphate or silicate levels start to climb again. Note: PhosGuard is not recommended for phosphate-buffered freshwater, because it would strip that buffer until it is saturated.
Features
Choose Your Size
| Spec | 100 mL | 250 mL | 500 mL | 1 L | 2 L |
|---|---|---|---|---|---|
| Treats Up To | ~60 gal | ~150 gal | ~300 gal | ~600 gal | ~1,200 gal |
| Best For | Nano tanks | Standard tanks | Reef & large FW | Big systems | Reactors & stores |
| Form | Beads | Beads | Beads | Beads | Beads (bulk) |
Coverage is approximate and depends on nutrient load. Media is consumed over time and should be replaced when phosphate or silicate creeps back up.
How to Use
Rinse PhosGuard before use, then place it in a fine media bag or a fluidized bed reactor where water flows through it. Begin with about 85 mL (one third cup) for every 200 L (50 US gallons). Test phosphate and silicate regularly and replace the media once levels start rising again. For best results, pair phosphate control with good carbon filtration and mechanical polishing.
Specifications
| Specification | Detail |
|---|---|
| Type | Phosphate & silicate adsorption media |
| Removes | Phosphate (PO4) and silicate (SiO2) |
| Form | Spherical porous beads |
| Starting dose | 85 mL per 50 gallons |
| Water type | Freshwater & saltwater (best in marine) |
| Use in | Media bag or fluidized reactor |
| Sizes | 100 mL, 250 mL, 500 mL, 1 L, 2 L |
| Brand | Seachem |
Pairs Well With
Build a complete clarity setup: run Seachem Matrix Carbon for dissolved organics, polish the water with a Seachem Tidal Polishing Pad, and keep tabs on nutrients with a Fritz Phosphate Test Kit.
FAQ
Will PhosGuard work in my freshwater tank?
Yes, but it is most effective in saltwater. Avoid using it in phosphate-buffered freshwater, since it will strip the buffer.
How do I know when to replace it?
Test phosphate and silicate. When the numbers start climbing again, the media is saturated and should be swapped out.
Do I need a reactor?
No. A media bag with good flow works well, though a fluidized reactor gives the most efficient contact.
Can I use it with carbon?
Absolutely. Many keepers run PhosGuard and activated carbon together for the clearest water.
Have a question?
Seachem PhosGuard
