How to automate a phytoplankton culture

In this article I will illustrate how to automate a phytoplankton culture, automation has been the key to successfully achieving stability in our hobby and with phytoplankton I feel that is no different. There is many reasons on how this could be beneficial not just in tank use but also in aquaculture aiding a more constant input of the lowest tropic level known to us and if used in conjunction with a rotifer reactor this should be able to deliver a stable amount of rotifers to a fish breading system.

To automate the phytoplankton culture you will a minimum of 1 dosing unit head.

the following pictures will be using two dosing unit heads although it can be just one if only partially automated or three if fully automated. Due to my current system being in the display I prefer to use the dosing pump to deliver the phytoplankton from the reactor to the display to avoid splashing on the wall and it looks a bit neater, the last step can also be achieved via gravity if the reactor is located in the sump were a few splashes won’t affect the safety of the use of the reactor.

Material list to build exactly what I have at the moment, there is several different ways that this ideology can be modified to perform the same way:

air pump
Dosing unit
Air line
Rigid air line
Fauna marine DIY reactor with a 800ml smooth surface bottle
Reservoir for salt mix
Natural sea salt
Fertiliser
Phytoplankton starter culture
K1 micro media or similar



step 1:

connect air line to the bottom of the reactor and use the provided check valve, this reactor got two air intakes one should be capped of with the supplied stopper and a additional check valve just to be safe.





Step 2:

Install the vessel as per manufacture instructions and remove the bottom of the vessel in a similar way to create a open top.





Step 3:

Add the lines from the tank to dosing unit and dosing unit to the phytoplankton culture, using heat try and create a hook kind of shape with the rigid air line.








the vessel lines should look like this




step 4:

Add a light source if mounted in the sump with a refugium light already in place additional light may not be required. The refugium light is normally sufficient.

step 5:

Add 500ml of a live phytoplankton culture of your choice and top up with a salt mix at 1.019 and fertiliser accordingly the volume of the culture.

Step 6:

Connect the line to salt water top up reservoir, I find that mixing it at 1.015 keeps a good balance to accommodate for evaporation in the culture, wile using the system further adjusting to the salinity of the top up salt mix may be required. The specific gravity of the top up salt mix will have to be adjusted depending on how much evaporation the vessel gets and how much phytoplankton is dosed daily.




step 7:

Add a few beads of k1 or k1 micro
This keeps the interior walls of the vessel clean and will allow better light penetration wile at the same time reducing maintenance to the vessel.





once all installed allow for 7 days for the culturing to strengthen and start setting your dosing unit. If the culture is already mature you should be able to start dosing from day 1.




It’s important that the same amount of phytoplankton out and top up saltwater in matches, if not the vessel will overflow.

As a safety feature one could add a third overflow line at the top of the phytoplankton culture in tevent of a malfunction and the top up saltwater mix is emptied in the vessel.

For systems larger than 25 gallons I normally start at a low dose, 1ml per hour or 24ml per 24 hours and allow the tank to adjust and slowly increase the hourly dose until I achieve my desired amount. Smaller thanks should start with a slower dose.

The dosing amount has to be adjusted on the phytoplankton out and saltwater top up in always to avoid overflowing the reactor.

fertiliser:

I do 1ml manually once every 7 days, this could also be automated.

I started using the fertiliser below as I believe it contain ingredients that could be useful to a reef tank in the situation that the fertiliser is not fully depleted by the culture, this will happen with most types of live phytoplankton cultures automated or manually. The end user should always consider this and choose a fertiliser they would be happy to dose directly to a system.



In general I’ve always had more successful cultures wend using natural sea salt it mixes at a lower dkh and ph, not absolutely sure on the advantage although my last culture went 2.5 years without maintenance or crashing.

this is the salt I’m using now




once all is set up it should look something like this, I’m normally not fond of having gear on display although I don’t have a alternative in this build, hopefully this information is helpful.