Phytoplankton question

[121]

I currently run my tank without a skimmer. If I added some phyto, would it multiply to the point of turning my tank dark green?

[djkms]

Doubt it. Between the organisms in your tank consuming it and bacteria out-competing it the phyto doesnt stand much of a chance. I turn my skimmer off for 8 hours after adding phyto to my tank and its gone in no time.

[121]

Does it really get consumed that fast by organisms?

If a skimmer is usually in use then any free swimming zooplankton (that might feed off phyto) would be permanently removed to begin with, leaving copepods on the glass and rocks.

I would assume it would take copepods weeks to catch a fraction of the phytoplankton dosed to a skimmerless aquarium.

Also, I've read reports of phyto increasing the nitrates and po4 in a tank. The culture will contain fertilizer to feed the phyto and the phyto contains no3 and po4 to begin with.

Would the use of phytoplankton increase the amount of free swimming zooplankton in a skimmerless tank?

[dzhuo]

Predation is only part of the reason why you are unlikely to see a huge bloom. The other is nutrient. Your tank wouldn't (normally) have the nutrient for a large bloom like this. Lighting is another factor, most of us runs lights toward the blue spectrum which don't favor phytoplankton.


Would the use of phytoplankton increase the amount of free swimming zooplankton in a skimmerless tank?


I think it will but is there a reason you want to dose phytoplankton explicitly? Most people don't need it and it could do more harm than good. Do you have a specific need?

[disc1]

The nutrients in the phyto can raise PO4 and NO3 levels. One fix is to rinse them through a coffee filter or other fine filter so you can rinse them in a little RODI.

If they go crazy and turn your water green, then you had bigger problems coming before you added phyto. Best to turn off the skimmer for a few hours while you feed, then have it come back on. Anything left in the water will get skimmed out.

[121]

Hi Dzhuo,

I only run T5 Blue+ but I have many tubes. I would assume all the tubes together will create enough PAR to cater for phytoplankton, seeing as only one yellow tube is needed to sustain a culture.

I'm going to culture phyto to feed brine shrimp. I would like to add it to my main display to boost the free swimming zooplankton and to expand the range of corals I can keep.

[121]

The nutrients in the phyto can raise PO4 and NO3 levels. One fix is to rinse them through a coffee filter or other fine filter so you can rinse them in a little RODI.

If they go crazy and turn your water green, then you had bigger problems coming before you added phyto. Best to turn off the skimmer for a few hours while you feed, then have it come back on. Anything left in the water will get skimmed out.

I have no nutrient problems. I currently only have chalice colonies and zoas with no fish, sand or skimmer. I don't feed the tank and have one piece of LR in my sump.

My corals are very healthy.

[dzhuo]

I only run T5 Blue+ but I have many tubes. I would assume all the tubes together will create enough PAR to cater for phytoplankton, seeing as only one yellow tube is needed to sustain a culture.


It's not about you don't have enough light. The lighting spectrum you have does not favor phytoplankton which means they will be outcompeted by other algae or micro-organism.


I'm going to culture phyto to feed brine shrimp. I would like to add it to my main display to boost the free swimming zooplankton and to expand the range of corals I can keep.

What corals you have in mind that requires constant supply of brine shrimp? Are you keeping NPS?

[121]

Hi,

Iirc, actinic bulbs do emit some of the PAR needed but the colour temp is predominantly blue for aesthetics. With enough actinic tubes, you can still give organisms enough PAR to function.

I would like to keep corals that eat phyto. the brine shrimp are cultured just to feed my fresh water fish.

[dzhuo]

Iirc, actinic bulbs do emit some of the PAR needed but the colour temp is predominantly blue for aesthetics. With enough actinic tubes, you can still give organisms enough PAR to function.

Hm. I guess I wasn't clear. :) I am not saying it's not enough PAR. I think different algae prefers different spectrum of light in order to thrive. With a predominately blue spectrum, it does not favor phytoplankton which could be another reason why you are unlikely to see a huge bloom. It's not uncommon to see hair algae or other types of micro-algae taking over a tank when the bulb's life is near its end shifting color temperature to yellow. This is just another example why color temperature is almost as important as PAR.


I would like to keep corals that eat phyto.


Softy are known to be a direct phytoplankton consumer but they rarely requires any special care as far as culturing phytoplankton goes. Are you plan to keep any NPS? Do you have any special need which requires higher phytoplankton concentration? I guess I am trying to convince you maybe you don't need to culture phytoplankton. :)

[121]

Dzhuo,

When a tube emits predominantly blue light, part of it is actually emitting the correct spectrum for PAR but this isn't visual due to the blue. With enough actinics, you can give corals and phyto the correct kelvin to sustain them. Iirc, they only use the small % of 6500k that they get from each actinic, but if you have enough actinic tubes...

[dzhuo]

121,
I understand that. The point I am trying to make is would your tank be a favorable environment for the phytoplankton to drive and take over? I think that's your original question: Whether the phytoplankton dosed directly into the tank would result in it's full bloom? I think the answer is no due to the various reasons listed above.