Copepods and Phytoplankton Question

[SeaHorseQueen]

I have a question. I know it's best to feed live phytoplankton but will the copepods eat dead phyto? I bought a bottle of Seachem Reef Phytoplankton because the store didn't have phytofeast. I want to get Ocean Magic from algae barn but will they eat any dead phyto until I get it shipped in? I have read they'll eat algae in general in the tank. Anyone done this?

 

[Spare time]

I think so.

 

[Reef Nutrition]

I have a question. I know it's best to feed live phytoplankton but will the copepods eat dead phyto? I bought a bottle of Seachem Reef Phytoplankton because the store didn't have phytofeast. I want to get Ocean Magic from algae barn but will they eat any dead phyto until I get it shipped in? I have read they'll eat algae in general in the tank. Anyone done this?

Yes, copepods will eat dead phytoplankton, among other things like organic waste and dry foods. There is a perception that live phytoplankton is best, but it's not true for the copepods that we put in our tanks. These are opportunistic animals just like corals and fish. We sell a Phyto-Feast Live with live algae if you are interested. It is also the most concentrated phyto on the market with more than 20 times as much algae as anyone else. This is something we specialize in. You can find our products on SaltwaterAquarium.com if your store is always out. They have free shipping when you spend a minimum. If you'd like to discuss this further, please let me know.

-Chad

 

[SeaHorseQueen]

Yes, copepods will eat dead phytoplankton, among other things like organic waste and dry foods. There is a perception that live phytoplankton is best, but it's not true for the copepods that we put in our tanks. These are opportunistic animals just like corals and fish. We sell a Phyto-Feast Live with live algae if you are interested. It is also the most concentrated phyto on the market with more than 20 times as much algae as anyone else. This is something we specialize in. You can find our products on SaltwaterAquarium.com if your store is always out. They have free shipping when you spend a minimum. If you'd like to discuss this further, please let me know.

-Chad

Thank you for clarifying! I bought the live tigger pods by your company. How often do you recommend feeding them phytofeast?

 

[DaJMasta]

It depends on the copepod, and generally, usage is less complete and the non-live version tends to have a different nutritional profile, but a lot of species will eat phyto concentrate and paste.

The live stuff tends to stay in suspension a bit better (though this depends on the phyto species), so a higher percentage of it probably gets eaten.

 

[Reef Nutrition]

Thank you for clarifying! I bought the live tigger pods by your company. How often do you recommend feeding them phytofeast?

Thanks so much for your purchase! We also thank you for supporting your LFS.

Most people will feed small amounts of Phyto-Feast once a day. We have dosage instructions on the bottle (1 TSP per 100 gallons per day). If you have corals and filter-feeding inverts, they will benefit from the phytoplankton. There are 6 species in the bottle, so you are getting a wide range of nutrition.

-Chad

 

[Reef Nutrition]

It depends on the copepod, and generally, usage is less complete and the non-live version tends to have a different nutritional profile, but a lot of species will eat phyto concentrate and paste.

The live stuff tends to stay in suspension a bit better (though this depends on the phyto species), so a higher percentage of it probably gets eaten.

I'm curious to know what you mean by "usage is less complete". I've been growing copepods on a commercial scale for 15 years and love talking about this subject.

Also, phytoplankton, no matter the species, mode of motility, or whether it's alive or not, will stay in suspension when there is current (hence the name "plankton" or "drifter"). It takes dead phytoplankton a long time (hours) to settle out if you turn off all the pumps in your tank (of course non-motile, live phyto will also settle. Nannochloropsis falls into this category and is the algal genus most commonly found in the hobby). I'm basically disagreeing with your comments about higher percentage of live phyto gets eaten versus dead phyto due to settling. I'm also curious if you've ever tested this.

-Chad

 

[fryman]

I'm curious to know what you mean by "usage is less complete". I've been growing copepods on a commercial scale for 15 years and love talking about this subject.

Also, phytoplankton, no matter the species, mode of motility, or whether it's alive or not, will stay in suspension when there is current (hence the name "plankton" or "drifter"). It takes dead phytoplankton a long time (hours) to settle out if you turn off all the pumps in your tank (of course non-motile, live phyto will also settle. Nannochloropsis falls into this category and is the algal genus most commonly found in the hobby). I'm basically disagreeing with your comments about higher percentage of live phyto gets eaten versus dead phyto due to settling. I'm also curious if you've ever tested this.

-Chad

I'm not sure if this is what Dajmaster meant, but you can definately feed large amounts of live phyto with little concern about waste , unlike dead phyto. I used to just put a week's worth of live phyto in at once, and this is no problem. Can't do that with dead phyto.

Also minor nit-pick but live phyto, motile or not, is able to maintain it's bouyancy regardless of current. I regularly keep live Nannochloropsis in stagnant buckets for a week and it remains in suspension. Only the dead cells will settle out at the bottom.

 

[SeaHorseQueen]

I'm not sure if this is what Dajmaster meant, but you can definately feed large amounts of live phyto with little concern about waste , unlike dead phyto. I used to just put a week's worth of live phyto in at once, and this is no problem. Can't do that with dead phyto.

Also minor nit-pick but live phyto, motile or not, is able to maintain it's bouyancy regardless of current. I regularly keep live Nannochloropsis in stagnant buckets for a week and it remains in suspension. Only the dead cells will settle out at the bottom.

How would I go about dosing dead phytoplankton until I get live in? I got one heck of an ammonia spike and I believe that’s where it’s coming from. Nitrite is 0 and nitrate is at 20 per API Master Kit.

 

[Reef Nutrition]

I'm not sure if this is what Dajmaster meant, but you can definately feed large amounts of live phyto with little concern about waste , unlike dead phyto. I used to just put a week's worth of live phyto in at once, and this is no problem. Can't do that with dead phyto.

Also minor nit-pick but live phyto, motile or not, is able to maintain it's bouyancy regardless of current. I regularly keep live Nannochloropsis in stagnant buckets for a week and it remains in suspension. Only the dead cells will settle out at the bottom.

I'm sure it depends on the density of phytoplankton you are adding to a tank, regardless of live or not. Our phytoplankton in our Phyto-Feast, which is dead, is 20-40 times as concentrated as a live phyto culture. This is really important to consider when feeding out concentrated phytoplankton. Equal portions of our dead phyto compared to live phyto are vastly different regarding biomass. Phytoplankton, alive or dead, will add organics to a system. Microalgae contains proteins just like animal foods. They algo get eaten and processed like any other filter-feeder food item. Saying that there is little concern about waste is not necessarily true here. Does this make sense? I do agree that it is hard to overdose a tank with live algae because there is only so much biomass a culture can produce and it's in a volume of water that would overflow your tank if adding more than a few liters at a time. Why can't you add the biomass equivalent of dead algae to live algae at once? I suppose it would take knowing the biomass of your live culture and comparing it to ours and feeding out accordingly. Tough to draw conclusions when we don't know these things.

Your suspension/settling comment may be true in some cases, but in our aquariums with water constantly moving, algae "settling" isn't going to happen. The cells get blown around with the slightest of currents. In your stagnate cultures, Nanno cells with high lipid content could be positively buoyant, but we expect them to slowly sink, still. Live cells under high light might produce O2 microbubbles that stick to them and keep them in suspension.

 

[fryman]

How would I go about dosing dead phytoplankton until I get live in? I got one heck of an ammonia spike and I believe that’s where it’s coming from. Nitrite is 0 and nitrate is at 20 per API Master Kit.

ime dosing every day very small amounts, or better yet multiple times a day. Just enough to turn water pale green. I would check to see if water clears in 24hrs and adjust accordingly. Optimally want water to stay tinted slightly green all the time but this is challenging. I think people overfeed more often than underfeed.

 

[fryman]

I'm sure it depends on the density of phytoplankton you are adding to a tank, regardless of live or not. Our phytoplankton in our Phyto-Feast, which is dead, is 20-40 times as concentrated as a live phyto culture. This is really important to consider when feeding out concentrated phytoplankton. Equal portions of our dead phyto compared to live phyto are vastly different regarding biomass. Phytoplankton, alive or dead, will add organics to a system. Microalgae contains proteins just like animal foods. They algo get eaten and processed like any other filter-feeder food item. Saying that there is little concern about waste is not necessarily true here. Does this make sense? I do agree that it is hard to overdose a tank with live algae because there is only so much biomass a culture can produce and it's in a volume of water that would overflow your tank if adding more than a few liters at a time. Why can't you add the biomass equivalent of dead algae to live algae at once? I suppose it would take knowing the biomass of your live culture and comparing it to ours and feeding out accordingly. Tough to draw conclusions when we don't know these things.

Your suspension/settling comment may be true in some cases, but in our aquariums with water constantly moving, algae "settling" isn't going to happen. The cells get blown around with the slightest of currents. In your stagnate cultures, Nanno cells with high lipid content could be positively buoyant, but we expect them to slowly sink, still. Live cells under high light might produce O2 microbubbles that stick to them and keep them in suspension.

I see your points. I'm just looking at things from a slightly different perspective. Live phyto is not going to add organics until it dies or gets eaten. Also live phyto will consume some waste so long as it stays alive.

I'm talking about copepod cultures. Feeding live keeps nitrate & phosphate very low in a rotifer, artemia, or copepod culture and I never have ammonia spikes unlike with preserved feeds. However this didn't work for me in my reef tank, for some reason. Feeding even large amounts of live phyto doesn't change measureable nutrients for me. I'm not sure why but my theory is that too many things eat it in the wild west biome of a typical reef tank. Phyto just doesn't seem to live long in a reef tank.

I'm relatively confident all live phyto does maintain bouyancy. But yeah this is probably a moot point since you need water circulation for other reasons.

 

[DaJMasta]

I'm curious to know what you mean by "usage is less complete". I've been growing copepods on a commercial scale for 15 years and love talking about this subject.

Also, phytoplankton, no matter the species, mode of motility, or whether it's alive or not, will stay in suspension when there is current (hence the name "plankton" or "drifter"). It takes dead phytoplankton a long time (hours) to settle out if you turn off all the pumps in your tank (of course non-motile, live phyto will also settle. Nannochloropsis falls into this category and is the algal genus most commonly found in the hobby). I'm basically disagreeing with your comments about higher percentage of live phyto gets eaten versus dead phyto due to settling. I'm also curious if you've ever tested this.

-Chad

Since it's still a live thread, I did actually run a basic test following that post as I hadn't run any specific tests before, but have definitely observed settling phyto (live and dead) as well as organisms which do not eat phyto that isn't alive (parvocalanus genus copepods, for example, haven't been successfully cultured on non-live feeds).

The test setup was basic: little vials had about 1mL of isochrysis galbana culture to them. One was a control with nothing else, one had half a drop of bleach to kill it, one was frozen for half an hour to kill it, and one was diluted with about 50% more RODI to kill it, and then I waited with them in a stable position to see if they settled. After a few hours I saw basically what I did at 7 hours and the next day, that the dead ones settled much more to the bottom (completely with bleach, mostly frozen, and little in the other two, I think perhaps the salinity shock wasn't enough to kill it), though all had some amount of sediment.

(Frozen, RODI added, Control, Bleach, left to right, 7 hours in)

I chose isochrysis because it tends to stay in suspension well in storage, both at room temperature and refridgerated, but as you've probably notice if you've worked with it, but tetraselmis (at least the species I've worked with) will settle even with modest agitation levels - if I don't heavily aerated my culture jugs (with a flat bottom), it accumulates there even when growing, and it's one of the first phytoplankton types to settle out when stored (even though it's motile). Then there are diatoms like chaetoceros gracillis which can't swim but which stay in suspension well and thalassiosira (the species I've worked with) which settle out quickly.

In any case, it was not a good sample size or a tightly controlled experiment, but I think it demonstrates the validity of the claim at surface value - a higher percentage of dead phyto settles out than live, though this may be less or negligible with nonmotile algaes or with certain species.

I don't think my comment about it not being used is inaccurate in the sense I meant, though I could have said it in a more specific manner: I, and I think most, feed phytoplankton to feed the creatures in our tanks which filter feed or which specifically eat phytoplankton. While the remainder that settles into the sediment or collects in a back chamber does still get eaten, it's detritus, and it likely will feed the same creatures as would be eating other kinds of food and animal waste that accumulates similarly.

Now to why I think you took issue with my claim: phytoplankton is pretty good at staying in suspension in the presence of flow, so it may be that the percentage of a dead phyto feed that goes unused by filter feeders and ends up as detritus vs. the percentage of live phyto that does the same is both not a huge chunk of the total amount fed to the system nor a dramatic percentage difference of the total amount that settles whether live or dead. As discussed above, with high flow situations I would expect that most of it stays in suspension for hours, at least, if not eaten until it finds some low flow nook or cranny in a tank to settle in. Even then, it's eaten by detritivores which may also be the sorts of copepods and things you were trying to feed when dosing phyto in the first place.

In the same vein of discussion, dead plankton foods also can't live in the water column (obviously), so there is no possibility of them multiplying to use up tank nutrients (though I'm not about to argue that the figure is a significant one), and when they settle out initially, there is no additional chance of getting back in the water column as with a motile algae (again, a small effect if a measurable one, probably). And it's probably not a huge difference, but I think it's perfectly reasonable to say it is a difference and that anyone inclined to try and quantify it to see if it should be an actual consideration should be encouraged to find out.

So while I don't think "The live stuff tends to stay in suspension a bit better (though this depends on the phyto species), so a higher percentage of it probably gets eaten." is inaccurate or even unintuitive, perhaps a more fully qualified version is: Live phytoplankton is more nutritious, more widely accepted by certain organisms, stays in suspension somewhat better (though perhaps not much better), and is thus is consumed in a higher portion by the filter feeding organisms we're trying to feed by offering phytoplankton to a tank (instead of the detritivores), but it may not be a significant enough benefit across the board to make it worth the extra expense and complexity over preserved phytoplankton feeds, at least for the majority of organisms we want to keep in our tanks.

My intention was never to complain about preserved phyto feeds, they are a better food source than dried versions or nothing at all from what I can tell, but I will still maintain that live phyto supplementation is the ideal option, even if it offers little additional benefit.

 

[SeaHorseQueen]

I’m currently using Seachem Phytoplankton. It says to use 5ml per 50 gallons twice a week. With my tank being 20 gallons, would I be safe to basically dose about a ml per day? Is it recommended to refrigerate it or room temperature? It’s dead so I imagine in the fridge would be better but this is the first time I’ve done this. It was sold on room temperature. I can say from experience, 2.5mls don’t change the tank water at all expect when first dropped in and immediately mixes with water. Do I want to basically add enough it starts to tint green or stick with directions on the bottle in my display tank? My 5 gallon culture, I can definitely deal with that turning light green but I don’t want dose too much in the display.

 

[SeaHorseQueen]

ime dosing every day very small amounts, or better yet multiple times a day. Just enough to turn water pale green. I would check to see if water clears in 24hrs and adjust accordingly. Optimally want water to stay tinted slightly green all the time but this is challenging. I think people overfeed more often than underfeed.

Would that be display or culture? Or can I do that both? I might be under dosing the phytoplankton.

 

[fryman]

Would that be display or culture? Or can I do that both? I might be under dosing the phytoplankton.

That was intended for a copepod culture. In a reef tank, I believe turning the tank water visibly green using preserved phyto would be way too much and lead to nutrient spikes. Live phyto won't do so unless there's excess fertilizer. I've dosed lots of live phyto into a reef tank and it will turn the water green for awhile but I don't detect a significant change in nutrients. I don't think many people do this because it's expensive.

Phyto dose is highly variable in the hobby. It's difficult to recommend a dose because density is a big factor and not standard. Dosing 1ml of concentrated preserved phyto (like phytofeast) is very different than 1 ml typical home-grown live phyto. My recommendation was by color, which I know is subjective. But I think it's typical practice at hobby level.

If the water has visible food, the copepods are probably not starving. It can be tricky to ensure there's not too much excess/waste. Most immediate/critical issue from overfeeding dead phyto is ammonia poisoning.

With live it's just not critical to avoid excess food, in my experience. But live is also a pita to grow and using just one type is not nutritionally balanced.

 

[Reef Nutrition]

In any case, it was not a good sample size or a tightly controlled experiment, but I think it demonstrates the validity of the claim at surface value - a higher percentage of dead phyto settles out than live, though this may be less or negligible with nonmotile algaes or with certain species.

I would definitely expect to see dead cells (lysed or fully intact) settle out in a completely stagnate environment when comparing to live Tisochrysis since it is motile. I agree that this is a surface value situation, but how would you prove this is happening in an aquarium? I hypothesize that, due to the incredibly small size of microalgae and all the current in our aquariums, phyto (alive or dead) is going to make its way into filters, crevices and piles of organic debris while it's getting fed upon by inverts. I can't imagine live algae being able to evade these areas long enough to outlast a dead phytoplankton cell. Even with great motility, like with Tetraselmis, it still gets knocked around by our pumps or even fish swimming by. We consider phytoplankton, alive or dead, to be food. How you feed it is incredibly important. A lot of people's problems with phytoplankton is overfeeding, especially with our product.

I appreciate this conversation. Thanks so much for engaging.

Chad

 

[Reef Nutrition]

I see your points. I'm just looking at things from a slightly different perspective. Live phyto is not going to add organics until it dies or gets eaten. Also live phyto will consume some waste so long as it stays alive.

I'm talking about copepod cultures. Feeding live keeps nitrate & phosphate very low in a rotifer, artemia, or copepod culture and I never have ammonia spikes unlike with preserved feeds. However this didn't work for me in my reef tank, for some reason. Feeding even large amounts of live phyto doesn't change measureable nutrients for me. I'm not sure why but my theory is that too many things eat it in the wild west biome of a typical reef tank. Phyto just doesn't seem to live long in a reef tank.

I'm relatively confident all live phyto does maintain bouyancy. But yeah this is probably a moot point since you need water circulation for other reasons.

We can control ammonia in a rotifer culture with a compound called ClorAm-X. This stuff is amazing. It neutralizes ammonia, among other things. We don't feed live algae to our rotifers and can get densities of around 1000/ml. I also don't feed live phyto to my Apocyclops panamensis or Tigriopus californicus cultures. These animals have a high tolerance for ammonia. Nitrate and phosphate aren't an issue either. Food is usually the bottleneck with copepod and rotifer culture. While live algae is a great food source for them and you can culture them like this indefinitely, you are limited by your microalgae production. With something like algae concentrates, you can produce more of these animals without expanding your live phyto production. Many people don't even grow algae to culture rotifers. They use our dead phytoplankton and manage the water quality of their cultures in a variety of ways. I suppose what I'm saying here is it's all in the way you do things; technique is huge in live feeds aquaculture.

I appreciate chatting with you, as always.

 

[TheMetalReefs]

I have a question. I know it's best to feed live phytoplankton but will the copepods eat dead phyto? I bought a bottle of Seachem Reef Phytoplankton because the store didn't have phytofeast. I want to get Ocean Magic from algae barn but will they eat any dead phyto until I get it shipped in? I have read they'll eat algae in general in the tank. Anyone done this?

cant tell you for sure but thats what i feed my pods. seems to be working, unless theyre surviving off of otherstuff in my tank.