The Spirulina has thrived now and it’s time to divide the culture a bit so that we have a backup culture in case the main one crashes.
This one will be kept at a lower temperature and with less light than the main culture so that it doesn’t grow as quickly. I’ll let the Spirulina in the main tank breed back up until there’s 20 litres in it before starting to divide it into smaller, 5 litre containers, one at a time.
The plan is to (eventually) have the culture in 8 of those big glass bottles with taps to make the harvesting easy. That’s a harvest from one bottle each day of the week with one spare to ensure that the Spirulina in each bottle gets back up to strength.
I’ll be leaving the initial tank outside in a protected position to see how Spirulina deals with the local conditions with only agitation. It was obvious that a new culture wouldn’t handle the Winter cold but now that things are warming up at night, I think its worth a try.