I started my culture from a sample of water gathered from a puddle that formed on the lid of the hot tub. I put the water in some jars, added some miracle grow, filled it to the brim with tap water, screwed the lid on tight, and left them alone on the back porch in the sun for a month (may of 2012 - it was a temperate month). This allowed the algae time to bloom and grow, while simultaneously allowing any undesirables (like mosquito larva) to die off. You may start a culture in a similar way or start with a sample obtained from anyone that has already grown a culture. It may be advantageous to grow algae that prosper in your local environment.

Once you have your starter, it's time to grow and propagate.

There are only a few requirements to keep the algae growing:
1) light
2) nutrients
3) water

Light:

I use a cheap reflector lamp from the hardware store and a full spectrum CFL bulb. Place the lamp right up against the jugs (or just a few inches away if you use plastic). By positioning the light between the jugs, you can provide high illumination to two jugs per lamp.

A sunny location will work also. Algae love light. Ideally you should have the light on 18 hours per day; however, I have not noticed any difference in growth between 18 hrs and 24 hrs. You can save electricity by turning the lights off when you go to bed and then on as soon as you wake, or just leave them on all the time like I do.

This is also where the bubbler and air stone come into play; place the air stone in the bottom of the jug and set the air flow so that the water appears to be gently boiling. This helps keep the algae in suspension and allows it to be constantly moving, so that all of it gets exposed to the light. The stirring provided by the bubbles allows you to grow much denser cultures than are possible without any water movement. You should not have the issues with foam that you might for marine phytoplankton. For freshwater algae cultures (greenwater) more air is better.

Nutrients:

I currently use F2 Medium. I have used miracle grow plant food and Enfamil powdered baby formula for fertilizer. I have experimented with lots of fertilizers and different concentrations, and to will continue to do so, but so far these two have been the best. The Baby formula provides micronutrients to the algae that I hope are ultimately passed on to the fish. Baby Formula is not strictly required, but have found that it helps a lot. F/2 culture medium works slightly better than miracle grow and baby formula, but per volume is much more expensive. 8oz of F/2 lasts me about 4 months. The box of miracle grow and tin of baby formula were used for almost 10 years and are still more than halfway full.

We have recently started mixing our own Guillard's F/2 culture medium - and offering it for sale.

Add nutrients every 3 to 5 days or when starting or splitting a culture.

Water:

Good water is important in all aspects of fish husbandry, but there are some details unique to algae cultures. You will need de-chlorinated water, or the chlorine will kill the microorganisms you are trying to grow. However, you also need relatively sterile water. Do not use water from an old aquarium or rainwater as you may introduce critters into your culture that will consume the algae. Tap water is better than RO or distilled water since it usually contains additional minerals that the algae can use.

I use tap water treated with Seachem Prime. My tap water is extremely hard and alkaline (pH=8.5+ and carbonate hardness of 30dKh+). If using RO water or very soft water it helps to add baking soda (1/2 to 1 tsp per gallon) or some KH or remineralizer to the water. One possible benefit to having alkaline water is that the miracle grow tends to acidify it, and with neutral (or slightly acid) water it may make it to too acid for good growth. Shortly after starting a new jug my culture has a pH of 6.8 to 7, as it matures the ph rises to 8.5 and stays there. If you know the pH of your starting water before adding the fertilizer, checking the pH is a good way to test and see if all (or most) of the fertilizer has been consumed. When using F/2 it doesn't seem to have the same PH effect.

Culture Process:

Day 1 of a new culture, I add about 1/3rd gallon of starter to my gallon jar, and then top with de-chlorinated tap water. I then add 1/8th tsp (.25ml) of miracle grow powder and 1/8th tsp (.25ml) of Enfamil powder or 5ml of F/2. Shake the jug to mix, then feed the airline trough the stopper and add the air stone. Set up your light and bubbler, and let it run.

Day 4, I add another 1/8th tsp (.25ml) of miracle grow powder (no baby formula is added this time), or 3ml F/2.

Day 8, harvest. Remove the cap and air stone, shake it to mix well, and then use/store/discard 2/3rds of the green water. Transfer remaining 1/3 to new cleaned jug and restart (day 1)

On your first harvest you can use some to start a new culture (back to day 1). If you only have one culture use 1/3 to start a 2nd bottle, 1/3 to keep the first going, and feed or discard the remaining 1/3rd. delay adding fertilizer to the second culture a few days so that you can stagger them, allowing you to harvest twice a week. You can delay harvesting for several days, but by day 8-9 I have usually reached maximum density. It is best to harvest at least 2/3rds every 8-12 days even if you do not need it at the time, so that the culture is fresh and growing when you do need it.

Please keep in mind that I use 1-gallon jugs for my cultures, if you use containers that hold more or less than 1 gallon, scale the amount of fertilizer and starter accordingly.

Notes:

- You can store the greenwater in the fridge for about a month if you shake it up every few days.

- LED lights will certainly work. I have found that the extra heat given off by CFL bulbs is beneficial. It grows faster when warmer.

- Light spectrum (10k vs daylight vs warm white) might not matter as much as other factors. Changing the light can slow growth for a short time, but in the longer term once it adapts to the new light it seems to grow just as well.

- Put some in a jar or bottle with a tight lid and set in a windowsill out of the way. This can be used to start a new culture months or years down the road if needed.

- Greenwater is hardy. It is much easier than Marine Phyto. Sanitation is important, but just rinsing everything with tap water is enough. It can usually outgrow contaminants as log as you split frequently and fertilize.

To get your own starter cultures check out the Links under "Buy Here"

Or contact us to see if more is available or for info on any project or culture. Please email us at contact@bluebladefish.com

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