Darren wrote to me after he had read my article on PMBS. One question asked by him was:

“ How to 'make' green water. Is it just by adding spirulina to the salt water?”

Darren, to benefit members here I have decided to answer your question in the forum, I hope you don’t mind. I will be posting my green water culture articles soon, the reason why I did not mention on the steps for culturing green water is there are many other used for green water, thus I thought it should be a separate write-up. But before I post up my write up, I hope this helps.

Green water culture is a live culture; they are living algae and thus will not foul the water. By adding spirulina to water will give you a “green color” solution and not a green water culture. Like most food, spirulina is non-living and will decompose thus causing bacterial growth (that’s how you got foul water) that is why some people store their spirulina solution in the refrigerator after preparing them.

Green water culture, on the other hand, is a living culture. It is very difficult to crash a green water culture, or rather almost impossible. (As long as there is light and food source (Fertilizer)

The Green water you find in your planted tank is the same green water culture I am talking about.

To culture green water, you need green water to inoculate, just pour a bit of green water into a container of tap water + fertilizer and leave it in the sun for about 7 days and you will have supper green water. I used to drop a few drops of fertilizer every few days but now I stop practicing that. I threw in a few snails and the snail droppings supplement the solution for me.

Uses of green water

You can use it to culture daphnia or feed the green water to your newly hatch fry. The green water culture promotes infusoria growth, which is small for your new babies if they are not ready for baby brine shrimp. You can also use it to grow you BS as mention in PMBS.

I hope this explain the question you ask.
Thanks Darren for correcting my grammatical mistake, I am always very poor in my language.

I wrote this based on my own experiences with green water, if any of you disagree with any part of the write up, kindly please inform me. I will do further research and check to ensure the accuracy of the write up.