Spirulina Grow Medium for 40L Spirulina Platensis culture. Complete pre-blended mineral solution with full mixing instructions. Makes 40 litres. UK-based supplier.
£24.99
https://www.agrifarming.in/growing-spirulina
https://www.wikihow.com/Grow-Spirulina-at-Home
https://thepowerofchi777.com/product/live-spirulina-culture-100ml/
Spirulina Grow Medium is a pre-blended mineral solution for cultivating Spirulina Platensis algae. This pack contains enough to prepare 40 litres of growing solution — the ideal amount for a medium-sized home tank.
Spirulina Platensis is a type of blue-green algae that grows in warm, alkaline water. It requires specific minerals for cultivation: carbon, nitrogen, potassium, iron, magnesium, and trace elements. This grow medium provides all of them in the correct proportions, so you can focus on temperature, light, and pH rather than mixing your own mineral salts.
This pack contains the following components, pre-measured and ready to mix:
Sodium bicarbonate — provides the carbon source and maintains alkalinity
Himalayan salt — supplies trace minerals and supports salinity
Mineral blend, consisting of:
Potassium nitrate — nitrogen source for cell growth
Monoammonium phosphate — phosphorus source for energy transfer
Iron sulfate — supports photosynthesis and pigment production
Potassium sulfate — potassium for cell function
Magnesium sulfate — supports chlorophyll production
Calcium chloride — supports cell wall structure
Everything is pre-weighed and blended, so you don’t need to source individual chemicals or work out ratios yourself.
Dosage: Use 17.5g per litre of water.
For 40 litres: Use the full pack.
For smaller volumes: Weigh out 17.5g per litre. For example, 10 litres of water needs 175g of medium.
Fill your container with water. Distilled water gives the best result, but tap water left to stand for 24 hours (to allow chlorine to evaporate) can also work.
Add the grow medium at 17.5g per litre.
Stir or agitate to help it dissolve.
Allow 12–24 hours for full dissolution. The medium may not dissolve immediately — this is normal. Agitation speeds up the process.
Check the pH. It should settle between 10 and 11.
Once fully dissolved and at the correct pH, add your spirulina culture.
Distilled water contains no chlorine, chloramine, or dissolved minerals that can interfere with the medium. Tap water can work, but the minerals already present may alter the final chemistry. If you use tap water, let it stand for 24 hours first, or use a water conditioner to remove chlorine.
Once your tank is running, you will need to top up the grow medium as you harvest spirulina. When you remove culture, replace the same volume with fresh medium at the same concentration — 17.5g per litre.
A healthy tank will need periodic medium replacement. As spirulina grows, it consumes the minerals in the water. When growth slows or the colour pales, it’s usually time to refresh the medium.
Q: What is Spirulina Grow Medium?
A: It is a mineral solution for cultivating Spirulina Platensis algae. It provides the minerals spirulina needs to grow in a home tank.
Q: How much medium do I need?
A: Use 17.5g per litre of water. This pack contains enough for 40 litres.
Q: How do I mix it?
A: Add 17.5g per litre of water, stir to help it dissolve, and allow 12–24 hours for full dissolution. Agitation speeds up the process.
Q: What water should I use?
A: Distilled water gives the best result. Tap water can be used if left to stand for 24 hours to allow chlorine to evaporate, or treated with a water conditioner.
Q: How long does it take to dissolve?
A: It can take 12–24 hours. This is normal. Stirring or using a small pump will speed it up.
Q: What pH should the medium be?
A: Between 10 and 11. Spirulina tolerates pH from 8 upwards, but slightly alkaline conditions work best.
Q: Do I need to add anything else?
A: No. This medium contains everything spirulina needs for cultivation. You only need to add water and your live culture.
Q: How often do I need to replace the medium?
A: When growth slows or the colour pales, it’s time to refresh. As a general guide, top up with fresh medium each time you harvest.
Q: Can I use this medium for other algae?
A: It is formulated specifically for Spirulina Platensis. Other algae have different requirements.
Q: How should I store the medium?
A: Store in a cool, dry place in its original sealed packaging. Keep it away from moisture.
Q: Can I mix a smaller batch?
A: Yes. Weigh out 17.5g per litre for whatever volume you need. For example, 10 litres needs 175g.
Q: Do I need a refractometer?
A: It’s useful for checking salinity, which should be between 15 and 20 PPT. But it’s not strictly essential for a first grow.
Q: What temperature should the water be?
A: 30–35°C is ideal for spirulina cultivation.
Q: Do you ship within the UK?
A: Yes. All orders are shipped from the UK. Please see our shipping policy for delivery times.
Q: Can I use this with your starter culture?
A: Yes. This medium is designed to work with our Live Spirulina Culture starter kit.
To cultivate spirulina, you will also need:
A live spirulina culture — see our starter kit listing
A container or tank — clear plastic or glass works well
A light source — natural daylight or a grow light
A thermometer — to monitor temperature
A pH test kit — to maintain alkalinity
Pre-blended and pre-measured — no need to source individual chemicals
Correct proportions — formulated for Spirulina Platensis
Makes 40 litres — suitable for a medium-sized home tank
UK-based supplier — shipped from the UK
Important: This product is a mineral solution for cultivating Spirulina Platensis algae. It is not a dietary supplement and is not intended for human consumption. Keep out of reach of children and pets. Store in a cool, dry place.
