Reef By Steele
10K Club member
How much phytoplankton does my aquarium need. This is a question that we receive often, and one that seems to have as many answers as the number of times it is asked.
So is there a correct answer? Yes, I believe there is, but this answer comes with a variety of considerations. I will lay out what we believe to be the basis for determining the proper dosing regimen, and the expected benefits associated with these recommendations.
First we need to determine what results we are seeking to achieve through adding phytoplankton to our aquariums. For us, we use phytoplankton for a variety of reasons, and they vary by aquariums. Here is our list.
1. Stimulate copepod reproduction and health within our ecosystem.
2. Provide a food source for a large variety of our tanks inhabitants.
3. Natural nutrient reduction.
4. Water quality, clarity, and conditioning.
COPEPOD PRODUCTION
Copepods consume a large variety of different kinds of food in our aquariums. This can include detritus, nuisance algae, left-over food, and phytoplankton. Of those listed, phytoplankton is by and far the best food source for them, based on the nutritional value available in the different strains. Copepods fed phytoplankton create more nutritious copepods, which in turn provides our fish with a better food source. Just as our diets are reflected in our health, feeding our copepods better food increases their health and reproductive capabilities.
FEEDING OUR TANKS
Dosing live phytoplankton in a reef tank will benefit almost if not all of the tanks inhabitants. From rotifer to cleaner shrimp, most crustaceans consume phytoplankton, improving shell strength, coloration and overall health. Filter feeders of all types will also benefit from live phytoplankton, from sponges, feather dusters, NPS corals, clams, scallops and other bivalves will show faster growth, and sharper coloration. This is highly important for gorgonia, sun corals and other species that don't depend on photosynthesis for their nutrition.
REMOVING NITRATES AND PHOSPHATES
Live phytoplankton continues to reproduce in our aquariums. They require CO2, nitrates, phosphates, and sometimes silicates to foster this growth. This makes phytoplankton the most natural method of nutrient reduction available in the industry. Helping us to mirror a more natural environment, more closely mirroring natural seawater.
BETTER WATER
The presence of live phytoplankton and it's interactions in the aquariums provides a number of other natural benefits to our water and its inhabitants. We notice clearer water when we are consistently dosing our systems with phytoplankton. We also find our ORP and pH stabilizes from the oxygen produced by the phytoplankton. An interesting fact is that the majority of oxygen produced on earth comes from the phytoplankton in our water bodies.
SO HOW MUCH TO ADD?
When I first started using phytoplankton regularly, I followed the recommendations of my mentor who I was purchasing from. His recommendations was at least 1 ml per gallon of system volume as a minimum. He also said that it is virtually impossible to overdose an aquarium with phytoplankton. When we started our business www.reefbysteele.com, as a hobbyist selling here on R2R we shared the same recommendations based on how it had been proper for our tanks. When we made the move from hobbyist to sponsor turning our hobby to a family owned small business we did our comparison shopping and found that there really wasn't any true industry standard. Following our personal use, recommended when we started we developed a dosage guide that we provide in all of our orders. But again this is anecdotal, and as we have continued to use it in our own aquariums, we have determined some markers to fine tune our dosage to each tanks specific needs.
Many suggest starting at lower levels and building up, but we find no down side to beginning with 1 ml per actual system volume per gallon. In tanks heavily stocked with corals we recommend bumping to 2 ml per gallon over a week to 10 days, and increasing to 3 ml per gallon for tanks with large numbers of filter feeders, or NPS corals (one could maintain a lower dosage here if target feeding those specific life forms). Now is when a person will fine tune their dosage levels to their specific tank needs. This will be done using different metrics and some will be personal preference vs empirical data. Number one though is empirical, we should all be testing our nitrates and phosphates, and as we see changes in these values we may find we need to adjust our dosage accordingly. When the nutrients begin to drop, we should reduce or plan to reduce the amount of live phytoplankton to achieve balance when our numbers reach our target goals. We definitely want to avoid bottoming out our nutrients to avoid disrupting the balance in our ecosystem. This is the easiest marker to set and gauge.
Next would be attempting to measure the benefits received from the phytoplankton. In the absence of a major water quality issue or event (ammonia spike, steel salinity swing or outside pollutant) or heavy predation, we expect that your copepod colony populations will increase with live phytoplankton. Corals and other life will grow faster and appear healthier, and nuisance algae will be reduced or eliminated.
Here is where subjective decisions will come into play. If you are pleased with the results in these categories at your current dosing, and find yourself having to reduce that level due to dropping numbers. You have a decision to make. Don't reduce the phytoplankton or increase your nutrients through a different method (feed more, use products like Brightwell NeoNitro and NeoPhos). If you choose the reduce phytoplankton method, which is our first recommendation, then monitor your tank to see if it has a negative impact on the inhabitants. If so you may want to bring the dosing levels back up and supplement the nutrients.
It is my opinion that personalizing your phytoplankton dosage to your specific tanks requirements will provide the best results over time.
please share your personal experiences and/or methods you use to find that sweet spot in your system.
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