I've been growing phytoplankton for about two years. The first 6 months were a breeze, splitting the cultures to grow more about once a week.

Original recipe

Then at MACNA XV I met Darrin of DT's Live Phytoplankton, who pretty much made me doubt my cultures were viable and possibly even contaminated. So I decided to start anew with fresh algae disks, to get the best possible product. From that day forward, I had problems. Some batches would last about 6 weeks of culturing, others barely a month. It was very frustrating.

I ordered new disks from Florida Aqua Farms, new Micro Algae Grow, and tried my best to have the cleanest equipment possible. I was very attentive to the batches, but something would go wrong on a regular basis. I never should have listened to Darrin! 

So I turned to Anthony Calfo asking for help. (Umm. He never replied, never noticing my thread.) Lots of people chimed in with their suggestions.

Discussion thread

In disgust, I didn't bother making any more for about 2 months perhaps. Then my clownfish started to lay a clutch of eggs every two weeks, and the only way I'll ever rear them is if I have live rotifers to feed them. And to have those, you have to have plenty of phytoplankton on hand. Evan (Quiksilver) has been growing it successfully for months on end, so we talked about his procedure. His routine is very simple, and he doesn't split it for a month or longer. It just doesn't crash!

Four weeks ago, I took a half bottle (1 liter) of his phyto as a starter culture. I added tap water mixed with salt to 1.019 specific gravity, until it was filled about 2" from the top of the bottle. I filled a second 2-liter bottle the same way.

5 ml of Miracle Grow All Purpose Plant food (fertilizer) was added to the bottle. This comes in a bottle in liquid form. If you do several bottles, 5 ml per bottle.

This mixture is placed in front of a 20w 2' 6500K Normal Output Fluorescent bulb for 16 hours a day and 8 hours of darkness. Rigid airtubing is inserted through the cap of the bottle, and an air pump gently bubbles around the clock.

Since my cultures would crash at 5 days, you can imagine how I held my breathe in anticipation.

Here is what it looked like, two bottles glowing green:

Every day, Evan takes the bottle between both hands and rotates it back and forth quickly for a few seconds to get the sediment in the bottle back into the water column. So I do the same now.

It bubbled for 3 weeks, never crashed and got darker and darker. Here is a bottle of it, next to a small bottle of DT's.

I split the culture about a week ago, taking one bottle and putting it in the fridge for my tank. The other bottle was split into three new bottles, and is doing well. I've added one more item to the newer recipe:

1 ml Kent's Essential Elements per bottle.

So far this is working perfectly, and I'm going to start culturing rotifers in the near future. I just wanted to share the process in case you are thinking about it as well.

Recipe recap:

Starter culture from someone (even DT's would work, I've been told)

Tap water mixed to 1.019 sg

5 ml Miracle Grow All Purpose plant liquid food

1 ml Kent's Essential Elements

Lighting 16 hours of light, 8 hours of darkness regulated with a timer

Steady bubbling of air via rigid tubing to the base of the bottle

Shaken slightly each day to stir up the solution from the bottom.

Split the culture every week or two weeks, saving half for your tank and half to start new bottles. Repeat forever. ;)

Happy reefing!