Phytoplankton crash

[Dee425]

My phytoplankton keeps crashing right after I start a new culture. It looks good for a day or two then it turns a light yellow color and never develops into the usual green color. My initial cultures did well for about three weeks and then the crashes started. I am using and reusing 2L soda bottles, 1ml of micro algae grow, SG of 0.017 and temp of around 68. Thanks for your help, I am getting very frustrated!! My clownfish just laid eggs and I am afraid that I will not have enough phyto to keep the rotifers going.

 

[Bearjohnson]

SG of 0.017?

 

[Dee425]

SG of 0.017?

Oops...I mean 1.017

 

[Bearjohnson]

Dang I thought for had an easy fix for ya. LOL

Without knowing your procedure, I can ask, do you sterilize the vessel and the air tube before you begin? Also do you sterilize the new vessels that you will be using when splitting a culture?

Are you using RODI water?

 

[Dee425]

I sterilize my bottles with rubbing alcohol and the same with the air tubes. I reuse the bottles and sterilize before using them.

I am using tap water with a declorinator.

 

[yankieman]

Double your micro algea grow maybe even triple it ,,, 1ml is not enough ,, and maybe raise the temp to closer to 78

 

[Bearjohnson]

I sterilize my bottles with rubbing alcohol and the same with the air tubes. I reuse the bottles and sterilize before using them.

I am using tap water with a declorinator.

If your not using RODI then you should certainly sterilize the water that you are using. You can do that in a microwave.

 

[Dee425]

I sterilized the bottles and tubing in vinegar and bleach, increased the fertilizer, and sterilized the water in the microwave. So far I have 6 bottles that have not crashed. Thanks so much for the advice. I am not sure which was the problem, but so far the combination seems to be working. Now if I could only get the fry to live longer than 48 hours I would be in good shape!

 

[chprieur]

I use 1/3 green water for 2 liters bottle + 1 ml fertilizer + 24/24H 60W T8 white

 

[Akshay]

This is too much technicality for me... Forget all this sterlization, boiling water, alcohol etc... just take your tank water.
A simple fix would be :
1. Massively increase your starter dose of the culture (that will just overwhelm any other micro growth).
2. Give good aeration.
3. Put the bottle in direct sunlight.