culturing phyto from DT's


New member
I think I've heard of this, but have any of you cultured phyto from DT's? I'd like to start culturing some phyto but I don't want to order a culture and all....What are your culturing methods or good references to methods? Thanks...:D
i have researched this a little bit and most people seem to use the culture starter dics and it possible or has anyone just dumped a bottle of dt's into a 2 liter bottle filled with 1.020 sw.

i read that on a small scale you dont need lights or an air pump... {i have these though} i read you can just set the bottles in a window or outside and open and shake{after you put the top back on!!!}the bottles daily -i would imagine you need like 5 inches of space on top for this to be could just open the top and squeeze the liquid to the top and then suck new air in and cap and shake.
It's usually better to culture different species of phyto in different containers instead of buying DT's and culturing from that. The reason is that some species will out-compete the others and you'll probably be growing one species instead of many.
Culturing DT's works fine (I have done it), but you don't end up with anything like DT's. It will be a mono-culture of nannochloropsis and will have a much lower cell density than DT's with, in all likelihood a higher dissolved nutrient content (as would any home grown phyto). Still, it's an inexpensive and easy way to get nanno. starting cultures.
thanks al

thanks al

thanks...i believe with the less dense cultures i would be able to use what i need without over producing or say that there is higher nutrient levels vs dt's...dt's say not alot is removed from skimming...i was thinking i couyld dose at my skimmer intake to get rid of the nutrients... does any of this make sence?
Peter - The problem with dosing at your skimmer intake is that the skimmer (if effective) will remove some/most of the phyto.

I grow 3 different types of phyto (NAN, NCP & TET) using a window sill and air pumps (yes you need air to promote circulation so the phyto doesn't settle to the bottom and die). Light is important and if you end up with a thick layer of phyto on/near the bottom of your bottle, the phyto is not getting enough light to grow.

I dose (via 24/7 drip into the refuge) about 1 liter per day. I have missed a few days lately for various reasons and I know that the skimmer did not "coat" as quickly or as thickly as when I normally feed phyto. Per my reading is that while the skimmer only pulls out protein, the phyto gets caught in the rising bubbles and some is removed "in error". I can't remember where that thread was but my unscientific observations confirmed this.

Peter, I should have mentioned that I started a rotifer culture to use up the excess phyto. At the present, I have 11 gallons of phyto on the go which will normally keep 3 to 4, 1 gallon rotifer cultures going as well as plenty of phyto for the tank.

Home-grown phyto will have some dissolved nutrients (ie. phosphate and nitrate) in the water. They will not be removed by skimming. The only ways to get rid of the excess nutrients are:
1. Let the culture grow until it depletes all the nutrients. This is a fine balance however as the phyto then quickly loses nutritional value.

2. Concentrate the culture by removing excess water and dissolved nutrients (eg. as by centrifuging). DT's uses some method to do this so as to minimize the excess nutrients present.

Many people use home-grown phyto. You just have to be careful not to overdose it.

Running a skimmer while dosing phytoplankton is probably not the best idea. If you take the time to examen the skimmate, you'll notice there's a lot of large particles in there, as well as "dust size" stuff.

I did a little experiment where I added baby fry food to the tank. This is very fine, powdery food. When dosing, the skimmer would eject a lot of very dark brown sludge. When I stopped dosing this, the skimmate turned lightish brown, and the ammount was only 1/2 of that before.
thanks everybody for the input...yes my skimmer is effective i'm running a euro reef es5-3 on a 55. maybei'll start turning off my skimmer when i add phyto and ignore dt's statement. well who wants to add phosphates to their tank,,,oh yeah dt's cost 15 bucks a bottle

so where is the line to stop spending money on dts and agree a lil phosphate isnt bad
back in the saddle

back in the saddle

ok ...i just started two cultures using the premium reef blend

. each culture consists of tap water sg 1.019 ,10ml of fresh dt's and 5ml of miracle grow liquid plant food
housed in 2 liters and supplied air.

lighting is 2-24" 20w bulbs got an ott-lite bulb at the depot so i didnt have to goto the lfs to get a 6500k bulb. got another old aqua rays fw/sw bulb

read about the miracle grow on melevs reef{ dont quote me on that}
that was 3 bucks and i can get it a home depot .

i have pics and will upload and keep updating
phyto density w/pics

phyto density w/pics

ok so i am seeing a very noticable darkening...using 2 20w bulbs.

whats the minumum level of density needed so i use up the there an easy way of checking this..?

should i try to acheive the same color { darkness} of a bottle of dt's ?

have updated pics
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It was a fun little science project for about a month and a half, but then it became a huge chore. The cultures need to be split too often and not on a particular schedule for any specific one and you really need to use what you make in about a week. I would only suggest this if you have a huge reef tank. It was just a big headache that left me with a bunch of miljugs that sat around for months till I threw them out.


ok... someone mentioned if i do not have enough light i will have a thick layer on the bottom. i think mine is a heavy dusting on the bottom. if the phyto crashes will it smell? will all the green "fall out " of the water column? i think with 2 20w bulbs i should be good. with double the average light used will mine reach max densistty before 3 weeks? how do others measure density? guessing game based on color? the first batch i split i am going to try no fert. to try and use up whats in there. sound good?