Phyto culture to replace water changes and chaeto

fryman

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Years ago I had a 120 gal well-established reef tank with alot of pukani live rock and a 4 inch sand bed. Phosphate control was my primary issue. In my recollection, nitrate levels were consistently low or undetectable. Perhaps it was all the live rock and/or sand bed. I used GFO but then switched over to chaeto and this worked very well.
I moved to S. Korea for a few years and only recently started getting back into the hobby. My current tank is a little 15gal, pretty immature at less than a year old. It's bare-bottom. Nitrate consistently creeps up to 20ppm before I do a water change, phosphorus is very stable usually 15-20 ppb (0.05 - 0.06 ppm phosphate). I don't have any phosphate control in place (other than coral). So, a completely different experience than before.

I am currently building a new setup with two tanks, total of 120 gallons, and have been experimenting with phyto in anticipation of the project. I want one of the tanks to have a lot of filter feeders. It will be awhile before this happens so right now I'm just trying out ideas with the phyto. One idea I had is to use a max density phyto culture for weekly water changes.
I know plenty of people have theorized about using phyto for nitrate/phosphate control (basically in place of chaeto), but since it's not a common practice I expect there are challenges to doing so. I've tested using a tetraselmis culture and thought I'd share my results.

FIrst thing I did was simply start a new tetraselmis culture in a 5 gallon bucket and measure nitrate and phosphorus levels over time. I used an api nitrate kit and hanna phosphorus ulr checker. Also I should note that I centrifuged the samples to separate out phyto prior to water testing, otherwise the green water would prevent accurate readings.
  • Day 0 - 5 gal fresh salt water 1.026 sg with 7.5 ml f2 fertilizer (recommended level per florida aqua farms):
    • Nitrate: 80 ppm, phosphorus: off scale (>200 ppb)
  • Day 4
    • Nitrate: 20 ppm, phosphorus: 8 ppb
  • Day 5
    • Nitrate: 20 ppm, phosphorus: undetectable (measured 0 ppb)
At this point phosphorus was undetectable by the hanna, so I added a few drops of neophos (phosphate supplement). I tested 2 days later.
  • Day 7
    • Nitrate: undetectable (< 10 ppm per api test kit), phosphorus: undetectable (0 ppb)
The culture appeared healthy and I split it. I suspect it would have crashed if I didn't (my cultures do not last more than a week without splitting or adding fertilizer).

Admittedly I should have tested more often but wasn't expecting the levels to change so rapidly. In particular the phosphate, it appears tetraselmis consumes phosphate very rapidly. Next week I'm planning to run it again a little more controlled with daily readings, and once nitrate gets below 10 ppm I can switch to a red sea nitrate pro kit to get more precision on the nitrate readings.

At any rate, it seems to me adding phyto culture to a reef tank would add significant nitrate to the tank, at least using tetraselmis and standard f/2 media. I know of tanks run at 20 ppm nitrate but it's not a natural level, and if I were to add large amounts of tetraselmis culture water to my tank I suspect it would depress phosphate but elevate nitrate levels unsustainably. However this can be controlled by adding additional phosphate to the culture. With adjustments I think I could create a culture with undetectable nitrate/phosphate, and therefore could add relatively large amounts of living phyto without adding nitrate or phosphate to the reef tank. Alternatively, I could shoot for whatever levels desired by tweaking the fertilizer elements in my culture (e.g. if the tank tends to run high nitrate, set the culture to 0 nitrate but some phosphate to continue feeding the phyto and bring down tank's nitrate level). The phyto would then serve the same purpose as chaeto or an algae turf scrubber for nutrient control.

So the theory is using this method as an alternative to both the typical weekly water change and a refugium with chaeto.
Crazy idea or perhaps workable? Have other people tried this, and if so what were the problems/challenges?

Anticipated/potential challenges:
  • Depletion of minor/trace elements by phyto culture. Can check this via ICP, then potentially address with supplements.
  • How stable/consistent is the culture? If I follow the exact same procedure, I'm hoping to get the same water parameters with the goal to do water changes and filter feedings in one relatively easy process. Water changes need to be stable and consistent, but adding a living organism to the mix will likely add variability.
  • Would the phyto get eaten too quickly or too slowly? My system will have a UV sterilizer, so if I want this would prevent a phyto bloom in the reef tank. That could be a problem at the beginning, before there were many filter feeders but after awhile with such a food source available filter feeders would explode and then maybe eat the phyto within hours, reducing its effectiveness as a chaeto alternative. I suppose I could still run a chaeto refugium, it's not like this is very labor-intensive and I know the method works.
 

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Very interesting read, thank you! I’ll put my little 2 cents on what I’ve experienced with my ~35 gal system. I have a chaeto fuge and have worked my way up to dosing 25 ml daily of live phyto. Strangely enough where your experiment found that it caused nitrates to raise Im having a horrible time getting mine about zero. I dose 2ppm nitrates a day, about to raise to 3 and still have undetectable levels. My phosphates stay consistent around 0.04-0.07. I am a heavy believer in heavy import heavy export. I feed frozen 1-2 a day and flakes whenever I think about it. Also reed roids every 3 days. I am a huge believer in live phyto. Hoping to start my own setup here soon so I can feed more without breaking the bank
 

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Interesting read. Im dosing 2ml daily of easyreef sps booster and sps evo and I have a real hard time getting nitrate above 0 (confounder being much gha in the tank).
 

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Just guessing, but I think the phyto wouldn't have a chance to grow and lower nutrients. It would be killed by your sterilizer, therefore raising the nutrient levels, and it would be removed by your skimmer, assuming you have one. Of course there are also filter feeders and pods that love phyto as well, they'll multiply in correlation to the amount of phyto.
 
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Just guessing, but I think the phyto wouldn't have a chance to grow and lower nutrients. It would be killed by your sterilizer, therefore raising the nutrient levels, and it would be removed by your skimmer, assuming you have one. Of course there are also filter feeders and pods that love phyto as well, they'll multiply in correlation to the amount of phyto.

TY for your input. I don't know if the phyto would have a chance to stay around for long, I also suspect it could be rapidly consumed. This is not necessarily a bad outcome though.

UV will not kill phyto, it just prevents it from multiplying. But if nothing eats it the phyto would eventually die and this could add nutrients back into the tank.

A skimmer will remove phyto, but I'm not planning to run one. There is space allocated just in case, but in my old tank with a large chaeto refugium there was no need. Every tank is different so for this one I'll have to see how it goes. I think a skimmer is very effective/nearly requisite on SPS-dominant systems but I'm not big into SPS; mostly like softies, filter feeders, and LPS. I do have a few SPS and they don't grow as fast I expect as they would in a more typical skimmed tank but they do alright and my softies grew so fast in my old tank you could practically see it happening.
 
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We used to dose a lot of live phyto and the issue we had was that once it got established and started multiplying, the reef became ugly and covered in brown phyto slime. We then stopped phyto and started carbon dosing to get a healthy bacterial population.
Cheers! Mark
 
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We used to dose a lot of live phyto and the issue we had was that once it got established and started multiplying, the reef became ugly and covered in brown phyto slime. We then stopped phyto and started carbon dosing to get a healthy bacterial population.
Cheers! Mark
TYVM that's very good info. I will look into carbon dosing, must admit I don't know much about it. That's like vodka, right? Or are biopellets preferable nowadays?

If you have a reference I should check out for info, would be appreciated but at any rate I really appreciate the advice.
 

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TYVM that's very good info. I will look into carbon dosing, must admit I don't know much about it. That's like vodka, right? Or are biopellets preferable nowadays?

If you have a reference I should check out for info, would be appreciated but at any rate I really appreciate the advice.
Both work fine. Biopellets are expensive though and you must have and maintain a reactor. So it’s just another expense and another piece of equipment. Vodka is easy. Or you can get something like NoPox from Red Sea. But a lot of companies make these products nowadays.
 

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To add to this conversation and perhaps introduce something different. Cryptic zones is something I’m toying with now. I loaded my sump with live rock and kept it dark. Lots of sponges and tube worms and who knows what else. My nitrates are around 5 and PO4 about .07. However I do do regular water changes and keep phosguard to keep PO4 as low as possible so I don’t know for sure if the cryptic zone is working or not.

 

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Years ago I had a 120 gal well-established reef tank with alot of pukani live rock and a 4 inch sand bed. Phosphate control was my primary issue. In my recollection, nitrate levels were consistently low or undetectable. Perhaps it was all the live rock and/or sand bed. I used GFO but then switched over to chaeto and this worked very well.
I moved to S. Korea for a few years and only recently started getting back into the hobby. My current tank is a little 15gal, pretty immature at less than a year old. It's bare-bottom. Nitrate consistently creeps up to 20ppm before I do a water change, phosphorus is very stable usually 15-20 ppb (0.05 - 0.06 ppm phosphate). I don't have any phosphate control in place (other than coral). So, a completely different experience than before.

I am currently building a new setup with two tanks, total of 120 gallons, and have been experimenting with phyto in anticipation of the project. I want one of the tanks to have a lot of filter feeders. It will be awhile before this happens so right now I'm just trying out ideas with the phyto. One idea I had is to use a max density phyto culture for weekly water changes.
I know plenty of people have theorized about using phyto for nitrate/phosphate control (basically in place of chaeto), but since it's not a common practice I expect there are challenges to doing so. I've tested using a tetraselmis culture and thought I'd share my results.

FIrst thing I did was simply start a new tetraselmis culture in a 5 gallon bucket and measure nitrate and phosphorus levels over time. I used an api nitrate kit and hanna phosphorus ulr checker. Also I should note that I centrifuged the samples to separate out phyto prior to water testing, otherwise the green water would prevent accurate readings.
  • Day 0 - 5 gal fresh salt water 1.026 sg with 7.5 ml f2 fertilizer (recommended level per florida aqua farms):
    • Nitrate: 80 ppm, phosphorus: off scale (>200 ppb)
  • Day 4
    • Nitrate: 20 ppm, phosphorus: 8 ppb
  • Day 5
    • Nitrate: 20 ppm, phosphorus: undetectable (measured 0 ppb)
At this point phosphorus was undetectable by the hanna, so I added a few drops of neophos (phosphate supplement). I tested 2 days later.
  • Day 7
    • Nitrate: undetectable (< 10 ppm per api test kit), phosphorus: undetectable (0 ppb)
The culture appeared healthy and I split it. I suspect it would have crashed if I didn't (my cultures do not last more than a week without splitting or adding fertilizer).

Admittedly I should have tested more often but wasn't expecting the levels to change so rapidly. In particular the phosphate, it appears tetraselmis consumes phosphate very rapidly. Next week I'm planning to run it again a little more controlled with daily readings, and once nitrate gets below 10 ppm I can switch to a red sea nitrate pro kit to get more precision on the nitrate readings.

At any rate, it seems to me adding phyto culture to a reef tank would add significant nitrate to the tank, at least using tetraselmis and standard f/2 media. I know of tanks run at 20 ppm nitrate but it's not a natural level, and if I were to add large amounts of tetraselmis culture water to my tank I suspect it would depress phosphate but elevate nitrate levels unsustainably. However this can be controlled by adding additional phosphate to the culture. With adjustments I think I could create a culture with undetectable nitrate/phosphate, and therefore could add relatively large amounts of living phyto without adding nitrate or phosphate to the reef tank. Alternatively, I could shoot for whatever levels desired by tweaking the fertilizer elements in my culture (e.g. if the tank tends to run high nitrate, set the culture to 0 nitrate but some phosphate to continue feeding the phyto and bring down tank's nitrate level). The phyto would then serve the same purpose as chaeto or an algae turf scrubber for nutrient control.

So the theory is using this method as an alternative to both the typical weekly water change and a refugium with chaeto.
Crazy idea or perhaps workable? Have other people tried this, and if so what were the problems/challenges?

Anticipated/potential challenges:
  • Depletion of minor/trace elements by phyto culture. Can check this via ICP, then potentially address with supplements.
  • How stable/consistent is the culture? If I follow the exact same procedure, I'm hoping to get the same water parameters with the goal to do water changes and filter feedings in one relatively easy process. Water changes need to be stable and consistent, but adding a living organism to the mix will likely add variability.
  • Would the phyto get eaten too quickly or too slowly? My system will have a UV sterilizer, so if I want this would prevent a phyto bloom in the reef tank. That could be a problem at the beginning, before there were many filter feeders but after awhile with such a food source available filter feeders would explode and then maybe eat the phyto within hours, reducing its effectiveness as a chaeto alternative. I suppose I could still run a chaeto refugium, it's not like this is very labor-intensive and I know the method works.
I use Ocean Magic Live phytoplankton from algae Barn. Never prevented me from Having to to do water changes or have refugium it does help tremendously though to feed the corals copepods and everything else
 
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fryman

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Very interesting read, thank you! I’ll put my little 2 cents on what I’ve experienced with my ~35 gal system. I have a chaeto fuge and have worked my way up to dosing 25 ml daily of live phyto. Strangely enough where your experiment found that it caused nitrates to raise Im having a horrible time getting mine about zero. I dose 2ppm nitrates a day, about to raise to 3 and still have undetectable levels. My phosphates stay consistent around 0.04-0.07. I am a heavy believer in heavy import heavy export. I feed frozen 1-2 a day and flakes whenever I think about it. Also reed roids every 3 days. I am a huge believer in live phyto. Hoping to start my own setup here soon so I can feed more without breaking the bank
I am hesitant to suggest since there's so many unknowns but...

I think you could safely increase phyto dose. Keep an eye on how things react and keep this with a grain of salt but imo, 25 ml phyto is not much assuming 35 gallons with significant livestock and you could probably increase this alot before having any impact. Question is, will the benefits outweigh the drawbacks?

Additional per my perspective:
If I added only 25 ml live phyto/day to one of my 1 gallon copepod cultures, it would remain completely clear. That's not nearly enough food for them. I actually dose 250ml/day which is enough to keep the culture a light green color. So...ramping up to 35 gallons - even allowing the commercial phyto is probably more dense than mine I just don't think 25 ml live phyto is having much of an impact. Just my 2c

Any rate, go slow. IMHO
 
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JosephM

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I am hesitant to suggest since there's so many unknowns but...

I think you could safely increase phyto dose. Keep an eye on how things react and keep this with a grain of salt but imo, 25 ml phyto is not much assuming 35 gallons with significant livestock and you could probably increase this alot before having any impact. Question is, will the benefits outweigh the drawbacks?

Additional per my perspective:
If I added only 25 ml live phyto/day to one of my 1 gallon copepod cultures, it would remain completely clear. That's not nearly enough food for them. I actually dose 250ml/day which is enough to keep the culture a light green color. So...ramping up to 35 gallons - even allowing the commercial phyto is probably more dense than mine I just don't think 25 ml live phyto is having much of an impact. Just my 2c

Any rate, go slow. IMHO
Oh yeah I definitely see where you’re coming from. I just gotta get some bigger syringes lol. And hopefully in the next couple weeks I can start culturing my own to keep costs down. I’ve definitely noticed a lot more feather dusters popping up since I’ve started though
 

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The top 100 meters of the ocean is primarily filtered by phyto. In a tank though, the biomass per cubic meter is much higher, and would need a much higher density of phyto.
 

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Years ago I had a 120 gal well-established reef tank with alot of pukani live rock and a 4 inch sand bed. Phosphate control was my primary issue. In my recollection, nitrate levels were consistently low or undetectable. Perhaps it was all the live rock and/or sand bed. I used GFO but then switched over to chaeto and this worked very well.
I moved to S. Korea for a few years and only recently started getting back into the hobby. My current tank is a little 15gal, pretty immature at less than a year old. It's bare-bottom. Nitrate consistently creeps up to 20ppm before I do a water change, phosphorus is very stable usually 15-20 ppb (0.05 - 0.06 ppm phosphate). I don't have any phosphate control in place (other than coral). So, a completely different experience than before.

I am currently building a new setup with two tanks, total of 120 gallons, and have been experimenting with phyto in anticipation of the project. I want one of the tanks to have a lot of filter feeders. It will be awhile before this happens so right now I'm just trying out ideas with the phyto. One idea I had is to use a max density phyto culture for weekly water changes.
I know plenty of people have theorized about using phyto for nitrate/phosphate control (basically in place of chaeto), but since it's not a common practice I expect there are challenges to doing so. I've tested using a tetraselmis culture and thought I'd share my results.

FIrst thing I did was simply start a new tetraselmis culture in a 5 gallon bucket and measure nitrate and phosphorus levels over time. I used an api nitrate kit and hanna phosphorus ulr checker. Also I should note that I centrifuged the samples to separate out phyto prior to water testing, otherwise the green water would prevent accurate readings.
  • Day 0 - 5 gal fresh salt water 1.026 sg with 7.5 ml f2 fertilizer (recommended level per florida aqua farms):
    • Nitrate: 80 ppm, phosphorus: off scale (>200 ppb)
  • Day 4
    • Nitrate: 20 ppm, phosphorus: 8 ppb
  • Day 5
    • Nitrate: 20 ppm, phosphorus: undetectable (measured 0 ppb)
At this point phosphorus was undetectable by the hanna, so I added a few drops of neophos (phosphate supplement). I tested 2 days later.
  • Day 7
    • Nitrate: undetectable (< 10 ppm per api test kit), phosphorus: undetectable (0 ppb)
The culture appeared healthy and I split it. I suspect it would have crashed if I didn't (my cultures do not last more than a week without splitting or adding fertilizer).

Admittedly I should have tested more often but wasn't expecting the levels to change so rapidly. In particular the phosphate, it appears tetraselmis consumes phosphate very rapidly. Next week I'm planning to run it again a little more controlled with daily readings, and once nitrate gets below 10 ppm I can switch to a red sea nitrate pro kit to get more precision on the nitrate readings.

At any rate, it seems to me adding phyto culture to a reef tank would add significant nitrate to the tank, at least using tetraselmis and standard f/2 media. I know of tanks run at 20 ppm nitrate but it's not a natural level, and if I were to add large amounts of tetraselmis culture water to my tank I suspect it would depress phosphate but elevate nitrate levels unsustainably. However this can be controlled by adding additional phosphate to the culture. With adjustments I think I could create a culture with undetectable nitrate/phosphate, and therefore could add relatively large amounts of living phyto without adding nitrate or phosphate to the reef tank. Alternatively, I could shoot for whatever levels desired by tweaking the fertilizer elements in my culture (e.g. if the tank tends to run high nitrate, set the culture to 0 nitrate but some phosphate to continue feeding the phyto and bring down tank's nitrate level). The phyto would then serve the same purpose as chaeto or an algae turf scrubber for nutrient control.

So the theory is using this method as an alternative to both the typical weekly water change and a refugium with chaeto.
Crazy idea or perhaps workable? Have other people tried this, and if so what were the problems/challenges?

Anticipated/potential challenges:
  • Depletion of minor/trace elements by phyto culture. Can check this via ICP, then potentially address with supplements.
  • How stable/consistent is the culture? If I follow the exact same procedure, I'm hoping to get the same water parameters with the goal to do water changes and filter feedings in one relatively easy process. Water changes need to be stable and consistent, but adding a living organism to the mix will likely add variability.
  • Would the phyto get eaten too quickly or too slowly? My system will have a UV sterilizer, so if I want this would prevent a phyto bloom in the reef tank. That could be a problem at the beginning, before there were many filter feeders but after awhile with such a food source available filter feeders would explode and then maybe eat the phyto within hours, reducing its effectiveness as a chaeto alternative. I suppose I could still run a chaeto refugium, it's not like this is very labor-intensive and I know the method works.
Wow very thorough investigative approach to this topic! I wanted to add one answer to one of your ending questions on the subject. Trace elements could be replenished using BRS Triton method trace elements or other brands of a similar product. Great topic conversation and approach to this.
 

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Years ago I had a 120 gal well-established reef tank with alot of pukani live rock and a 4 inch sand bed. Phosphate control was my primary issue. In my recollection, nitrate levels were consistently low or undetectable. Perhaps it was all the live rock and/or sand bed. I used GFO but then switched over to chaeto and this worked very well.
I moved to S. Korea for a few years and only recently started getting back into the hobby. My current tank is a little 15gal, pretty immature at less than a year old. It's bare-bottom. Nitrate consistently creeps up to 20ppm before I do a water change, phosphorus is very stable usually 15-20 ppb (0.05 - 0.06 ppm phosphate). I don't have any phosphate control in place (other than coral). So, a completely different experience than before.

I am currently building a new setup with two tanks, total of 120 gallons, and have been experimenting with phyto in anticipation of the project. I want one of the tanks to have a lot of filter feeders. It will be awhile before this happens so right now I'm just trying out ideas with the phyto. One idea I had is to use a max density phyto culture for weekly water changes.
I know plenty of people have theorized about using phyto for nitrate/phosphate control (basically in place of chaeto), but since it's not a common practice I expect there are challenges to doing so. I've tested using a tetraselmis culture and thought I'd share my results.

FIrst thing I did was simply start a new tetraselmis culture in a 5 gallon bucket and measure nitrate and phosphorus levels over time. I used an api nitrate kit and hanna phosphorus ulr checker. Also I should note that I centrifuged the samples to separate out phyto prior to water testing, otherwise the green water would prevent accurate readings.
  • Day 0 - 5 gal fresh salt water 1.026 sg with 7.5 ml f2 fertilizer (recommended level per florida aqua farms):
    • Nitrate: 80 ppm, phosphorus: off scale (>200 ppb)
  • Day 4
    • Nitrate: 20 ppm, phosphorus: 8 ppb
  • Day 5
    • Nitrate: 20 ppm, phosphorus: undetectable (measured 0 ppb)
At this point phosphorus was undetectable by the hanna, so I added a few drops of neophos (phosphate supplement). I tested 2 days later.
  • Day 7
    • Nitrate: undetectable (< 10 ppm per api test kit), phosphorus: undetectable (0 ppb)
The culture appeared healthy and I split it. I suspect it would have crashed if I didn't (my cultures do not last more than a week without splitting or adding fertilizer).

Admittedly I should have tested more often but wasn't expecting the levels to change so rapidly. In particular the phosphate, it appears tetraselmis consumes phosphate very rapidly. Next week I'm planning to run it again a little more controlled with daily readings, and once nitrate gets below 10 ppm I can switch to a red sea nitrate pro kit to get more precision on the nitrate readings.

At any rate, it seems to me adding phyto culture to a reef tank would add significant nitrate to the tank, at least using tetraselmis and standard f/2 media. I know of tanks run at 20 ppm nitrate but it's not a natural level, and if I were to add large amounts of tetraselmis culture water to my tank I suspect it would depress phosphate but elevate nitrate levels unsustainably. However this can be controlled by adding additional phosphate to the culture. With adjustments I think I could create a culture with undetectable nitrate/phosphate, and therefore could add relatively large amounts of living phyto without adding nitrate or phosphate to the reef tank. Alternatively, I could shoot for whatever levels desired by tweaking the fertilizer elements in my culture (e.g. if the tank tends to run high nitrate, set the culture to 0 nitrate but some phosphate to continue feeding the phyto and bring down tank's nitrate level). The phyto would then serve the same purpose as chaeto or an algae turf scrubber for nutrient control.

So the theory is using this method as an alternative to both the typical weekly water change and a refugium with chaeto.
Crazy idea or perhaps workable? Have other people tried this, and if so what were the problems/challenges?

Anticipated/potential challenges:
  • Depletion of minor/trace elements by phyto culture. Can check this via ICP, then potentially address with supplements.
  • How stable/consistent is the culture? If I follow the exact same procedure, I'm hoping to get the same water parameters with the goal to do water changes and filter feedings in one relatively easy process. Water changes need to be stable and consistent, but adding a living organism to the mix will likely add variability.
  • Would the phyto get eaten too quickly or too slowly? My system will have a UV sterilizer, so if I want this would prevent a phyto bloom in the reef tank. That could be a problem at the beginning, before there were many filter feeders but after awhile with such a food source available filter feeders would explode and then maybe eat the phyto within hours, reducing its effectiveness as a chaeto alternative. I suppose I could still run a chaeto refugium, it's not like this is very labor-intensive and I know the method works.
What's this f2 fertilizer? Do you have a link?

Have you experimented with other species of phyto? Thanks!
 

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I grew phyoplanton & copepods, and rotifers. The phyoplanton took over my 180 tank it grew on my rocks and everywhere on my glass. Took a long time for my tank to clear up. I probably was dosing my tank to much phyoplanton . Either way I would never stop doing water changes for the health of my fish and corals
 
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What's this f2 fertilizer? Do you have a link?

Have you experimented with other species of phyto? Thanks!
Guillard's f/2 is a fertilizer specifically designed for culturing phytoplankton. I get mine from floridaaquafarms.com but there are lots of places that sell it.

For about a year I cultured large quantities of nannochloropsis, isochrysis (T-iso) and tetraselmis. I also have tried out Thalassorira and Porphyridium in smaller batches but was trying to set up continuous cultures and they crashed after a couple months. It looked pretty cool for a little while (see attached pic).

In my experience, tetraselmis is the easiest and most reliable. I know everyone says nanno is the easiest but that has not been my experience. The tet I used in this experiment was started from a 250ml starter left in my fridge for at least a year. I put it into a 5 gallon bucket and it started right back up. Try that with nanno (I have - it did not work out)... Which also leads to the primary reason I used tetraselmis for this - it's the only strain I currently have on hand because none of my other starters were viable. So... yeah I might try starting up some others again but would have to buy them so right now all I have to work with is tetraselmis. But this strain I have seems to be practically bulletproof so I figured it would be the best option anyway.

contunous culture experiment.jpg
 
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fryman

fryman

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I grew phyoplanton & copepods, and rotifers. The phyoplanton took over my 180 tank it grew on my rocks and everywhere on my glass. Took a long time for my tank to clear up. I probably was dosing my tank to much phyoplanton . Either way I would never stop doing water changes for the health of my fish and corals
TY, Daddy-o had a similar experience, so that seems to be something to watch out for. Dosing a ton of phyto may not be a good idea, at the very least until I have a lot of filter feeders. Even then it looks that I may have to watch out for the phyto settling out on substrate - something I hadn't really considered.

I'm not proposing an elimination of water changes, the water change would be included in phyto feeding. Similar to a typical weekly water change I would remove 5 gallons water and replace with 5 gallons of "phyto-infused" salt water that had been mixed 5-7 days previously and used to grow phyto.
 

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TY, Daddy-o had a similar experience, so that seems to be something to watch out for. Dosing a ton of phyto may not be a good idea, at the very least until I have a lot of filter feeders. Even then it looks that I may have to watch out for the phyto settling out on substrate - something I hadn't really considered.

I'm not proposing an elimination of water changes, the water change would be included in phyto feeding. Similar to a typical weekly water change I would remove 5 gallons water and replace with 5 gallons of "phyto-infused" salt water that had been mixed 5-7 days previously and used to grow phyto.
Are you in Belmont Ca?
 

A worm with high fashion and practical utility: Have you ever kept feather dusters in your reef aquarium?

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