Copepod Culturing

Copepod Culturing

Copepods culturing at home is easy but has received a bad reputation in the past from people that try to grow copepod using live algae or artificial feeds. Live algae requires too much water turnover and can typically only produce low densities due to the small volume of algae in the water, and artificial feeds will quickly foul the culture. Use a concentrated microalga to eliminate both these problems.

This is a simplistic method of maintaining a live copepod population at home. There are more sophisticated methods that can be set up once the basics have been mastered.

Copepod feed best on microalgae, typically in the 1 to 10 micron range. The most commonly used algae is called Nannochloropsis, a small green non-motile (non swimming) cell that is high in protein, carbohydrates, and lipids. Copepods have a very high metabolism and need to eat regularly.

Fortunately this is easy to do by keeping a supply of quality microalgae in the water with them.

Microalgae concentrates like NutriSpring Liquid 60 can be added to the water once or several times each day to maintain a healthy culture of copepods. Simply add a few drops of NutriSpring Liquid 60 to the tank until you have a light green colour. If the tank still has a light green colour at the next feeding you are adding the right amount. If not add a bit more algae each time until there is a residual colour. The most common practice is to feed the copepods in the morning and the evening.

Basic Components:

20 Litre bucket or larger tank
Air stone (set on low)
Dechlorinated salt water – Temperature 23-26 C is best with 1.019-1.025ppt salinity
Live copepod culture
Microalgae (NutriSpring Liquid 60 or Lyophilized powder are best)

Key Strategies:

Keep enough microalgae in the system so that the copepods always have food.
Harvest at least 20% of your culture and water every day.
Your copepod culture system must be set up in a stand-alone tank – they cannot be raised in a reef tank or co-cultured with other organisms. Harpacticoid copepods are benthic (on the walls of your bucket).

Starting your culture:

1. Place the copepod starter culture in the bucket of sterilized saltwater to acclimatize.
2. After 10 minutes, open the bag and gently introduce the copepod starter culture.
3. Maintain a light green color between feedings by adding approximately 2-3 ml of Liquid 60 daily per million rotifers.
4. Starting from day 3, harvest a minimum of 20% of your culture each day.

Harvesting Your Rotifers to feed a Reef Tank, Mandarin, Reefugium:

Before harvesting your copepod remove the airline and let sit for 10-15min. This will ensure any algae pieces and detritus sink to the bottom. After taking what you need, siphon some of (algae & detritus) from the bottom this will keep the culture clean and running continuously for many months. This will not damage the copepod at all.

• Harvest 20-30% of your copepod culture. This is best done by siphoning into a separate bucket and through plankton mesh of around 50 micron.
• Do not add the siphoned culture water to your aquarium as this could be high in ammonia.
• Turn off your skimmer but leave your pumps running.
• Place your copepods directly into your reef tank.
• Siphon water from your reef tank through the 50 micron plankton mesh back into your copepod tank to replenish the water.

Harvesting Your Rotifers to feed Fish Larvae:

• Turn off your air stone for 5-10 minutes. This will allow the detritus to settle.
• Harvest as many copepods as you need by the same method outlined above.
• Replenish the culture water by the same method outlined above. If you don’t have a reef tank you will periodically need to clean your culture tank to prevent the detritus levels from building up and causing ammonia spikes.

Tips:

• Copepod do not really need any light and will do best in the dark
• Do NOT let the copepods ever run out of food. It will take a few days for the eggs to hatch, and build to sufficient numbers for you to harvesting again.
• It’s difficult to measure your copepod densities without a microscope, so it might take 2-3 weeks before your find an equilibrium in your system for how much algae to feed and how many litters of rotifers to remove each day without affecting your culture densities.