Phytoplankton Culture Keeps Crashing

[JSLove]

I am completely new to the hobby and I'm probably making all kinds of mistakes, but learning on the way. I have been trying to culture phytoplankton and copepods for my tank and I'm having mixed success. The copepods seem to be thriving, but I've continually failed with the phytoplankton cultures. I have followed just about every video on Youtube and checked the forums, but I still can't seem to get it right. I'm currently using a live phytoplankton culture from Dinkins aquatics. They usually crash after about the 4th or 5th day and I usually have pretty bad settling despite very good aeration. I'm adding about 1.5 ml of F2 and this past time I made sure the sterilize everything before trying again. Here are some pics of my setups. Although one of the setups looks okay the other has significant settling at the bottom and is starting to turn.

Also when should I split my cultures? I haven't made it to that step because I usually have a total collapse after about a week. Thanks for your time.

 

[tzabor10]

What type of saltwater do you use to start? Are you keeping the water topped off to account for evaporation? Any chance your disinfectant is still on the jars?

 

[JSLove]

Thanks for your reply. I'm starting with saltwater that is 1.020. I'm not topping off water since I've never made it past a couple days. I was pretty thorough to make sure the disinfectant was removed this time. I'm wondering if either the light is too powerful or it could be with the phytoplankton culture itself. I'm currently trying it with Dinkins live phytoplankton blend.

here is the phytoplankton culture I'm using.
https://dinkinsaquaticgardens.com/products/live-phytoplankton-six-species-blend

 

[salty joe]

I'm wondering if either the light is too powerful

I'm thinking not enough light. The culture is shaded by the lid on the jar.
FWIW, I use a 14W, (100w equivalent) LED light bulb in direct contact with the culture bottle. The intensity of artificial light drops off in a hurry.

 

[JSLove]

In case anyone is reading this, I found the problem. The light was far too strong and was killing my phytoplankton. I switched to a less powerful light source and I'm having success now.

 

[jsmkmavity]

 

[MajorDad74]

In case anyone is reading this, I found the problem. The light was far too strong and was killing my phytoplankton. I switched to a less powerful light source and I'm having success now.

What light did you use? I’m struggling with phyto as well.

 

[ShakeyGizzard]

Thanks for your reply. I'm starting with saltwater that is 1.020. I'm not topping off water since I've never made it past a couple days. I was pretty thorough to make sure the disinfectant was removed this time. I'm wondering if either the light is too powerful or it could be with the phytoplankton culture itself. I'm currently trying it with Dinkins live phytoplankton blend.

here is the phytoplankton culture I'm using.
https://dinkinsaquaticgardens.com/products/live-phytoplankton-six-species-blend

I would not culture blended phyto, I use individual species. Dinkins does not offer you this option, Reef By Steele does. I would get a green such as tetraselmis chuii, and red such as rhodomonas lens. You can blend after harvest before adding to tank or pods. Keep the species seperated .