Is a live culture of phytoplankton needed for clownfish breeding? Not completely nessessary any more. With so many Rotigrow, Rotifeed, & Rotidiet products out there, you can pretty much grow rotifer solely on using those commercial product. But with limited budget, I rather grow phyto myself. The only thing that I will have to continue to buy is just the salt and some fertilizer.

There are 3 most common/popular phyto and they are Nanochloropsus, Tetraselmis and Isocrysis. They all have slightly different nutritional profile. If you only have room to grow just one culture, Nano would be the easiest and have enough nutrition for most cases.

I ordered my algae disks from [URL="]Florida Aqua Farms[/URL] (FAF). Soak them in 1.018 salt water for a day and pour them into a 2L soda bottle and fill it up with salt water. Put about 15-20 drops of fertilizer in there as well. Don't be cheap and use the fertilizer for normal plants. Get the MICRO ALGAE GROW from FAF. It uses the guillard F/2 formulation. Your larvae/fish will be eating it (indirectly) after all.


Drill the soda bottle cap and insert a rigid air tube in there. Connect it to an air pump and have it bubbling away. With Nano, you want the bubbling rate to be like boiling water. With Tetra and Iso, you want it to be a bit slower. If you don't have much space, just put the 2L bottles along with some light fixture in a bucket will do.


If you have some room, do it the right way. :D


FAQ: You can buy the rigid air tube from most fish store. It should be in their air pump section. I got mine from PetSmart. The rigid air tube is about 3 feet long. I cut them in half at 45 degree. And then cut off the pointy tip to make it less sharp. The reason to cut it at 45 degree is that if you cut it flat, when the tube is straight down the bottle, the air would get blocked by the bottle bottom.
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Harvesting Phytoplankton

Lot of people having problem keeping the culture going. This is the procedure I do and hope it can help out everyone to keep your phyto culture going.

For fertilizer, I use MICRO ALGAE GROW? GUILLARD F/2 FORMULATION from Florida Aqua Farms. Do not use Miracle Grow! It will work and phyto will grow, but it will also pollute your fish tank. Think about it, would you pour some fertilizer into your fish tank?

Prepare a few bottles of salt water at 1.018 ahead of time. Age it.

Put 15-20 drops of F/2 into one bottle of aged salt water that you are about to use. Shake well. (Do not put too much F/2. Too much of it actually would slow down the growth!)

Pour out 1/4-1/3 of the mother culture. You can either use it for feeding or start a new culture. Then refill the mother culture with the pre-mixed salt water with F/2. Since the culture only need to regrow that 1/4-1/3, it'll be ready to harvest again in just a few days.

If you are splitting and starting a new culture, simply use that 1/4-1/3 from the mother culture, put into a clean bottle and fill it up with the pre-mixed salt water with F/2. Bubbling away and the new culture should be ready in 7 days or so.
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I had a few conversations with a few people regarding the absolutely minimal to keep a phyto culture going. I think many other people would be interested as well, so here it is.

1 rigid air tube
2 2L soda bottles with 1 bottle cap drilled to let the rigid air tube in
1 pump and some air host
1 strip of work light
1 5g bucket to put everything in there
Some Fertilizer

That's all. One 2L soda bottle is for the culture and the other 2L bottle is to prepare new salt water and mixing a little fertilizer.

If you have a 2L culture, you can harvest 1/5-1/4 of it right away. Refill the bottle with your pre-mixed salt water (with fertilizer). By next day (or 2, depends on how strong your light is), the culture will be all green again.

If you are starting with just 1/2L of the culture, it'll take a week to 10 days to get the whole bottle green. Thereafter, just harvest and refill like I mentioned.

Easy enough? :)
OK. Start from scratch it is.

Cleaned up the totally abandoned phyto station. The white balance from iPhone photo doesn't look right at all. I checked each light with a PAR meter and most of them are still working well. The good ones give about 750 PAR and the bad ones still giving out 450 PAR.


Found a set of abandoned and untouched bulk size F/2.


Prepared some water at 1.019.


and a brand new Phyto Disk from FAF.

Here are the progress results:

Day 1 - right after dumping the soaked phyto petri dish into the bottle.


Day 2


Day 2 - Original culture with a little experiment with the clear bottle on the side. The clear bottle is intentionally "contaminated" with a small splash of phyto from the other bottle.


Day 3 - The original culture along with the "contaminated" clean water (after 24 hours)


Day 3 - Same day 3 but with an actually clean bottle alongside for comparison.


Day 4 - Original culture, contaminated bottle, and clean water


That's all. The original culture is about dense enough to split again.

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