Coco peat is sold by weight but used by volume, so the number that matters when you plan a crop is how many litres you get. The calculation is simple once you have the expansion figure for the product and grade.
The formula
Litres = block weight in kg × expansion in litres per kg
For a 5 kg Low EC Standard block at 13 L per kg, that is 5 × 13 = 65 litres of loose media.
Volume per 5 kg block
These figures are calculated from the per-kg specification. Exact values are confirmed on the quotation.
| Grade | Low EC, per kg | Low EC, per block | High EC, per kg | High EC, per block |
|---|---|---|---|---|
| Fine | 16 L | 80 L | 14 L | 70 L |
| Standard | 13 L | 65 L | 11 L | 55 L |
| Coarse | 10 L | 50 L | 9 L | 45 L |
Working out how many blocks you need
Start from the total volume you need to fill, then divide by the litres per block.
Example: grow bags. You have 1,000 grow bags that take 10 litres each, using Low EC Standard.
- Total volume: 1,000 × 10 = 10,000 litres
- Blocks needed: 10,000 ÷ 65 = 153.8
- Round up to 154 blocks
Example: raised beds. You need 2,000 litres of High EC Coarse for bed preparation.
- Blocks needed: 2,000 ÷ 45 = 44.4
- Round up to 45 blocks
Add a margin on top, because loose media settles once it is watered and handled.
Checking expansion yourself
A simple test tells you what a delivery really gives.
- Weigh a piece of block and note the weight.
- Place it in a large container and add water slowly until it has fully expanded.
- Break it up so no compressed lumps remain.
- Fill a measuring container with the loose media, without packing it down.
- Divide the litres by the starting weight in kilos.
Use the same method every time. Pressing the media into the measure gives a lower reading, so the value of this test is in comparing one batch with the next.
Expansion is also linked to moisture, because water in the block adds weight without adding volume. Read how moisture content affects coco peat quality for more.
Ready to price a quantity? Request a bulk quote with the product, grade and volume you need.
