Tips for Growing Isochrysis

beesnreefs

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We’ve been culturing live phyto for a few months. Have a lot of success with Nanno, Tet, and Porphyridium. Isochrysis seems hit or miss. Seems like every other culture of Iso crashes.

We use the PoseidenReefSystems reactors with single-use bags. Isopropyl alcohol to clean everything between cultures, gloves for cleanliness. Iso starter cultures have come from Algae Research Supply.

Any tips specific to Isochrysis cultures?
 
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@Eldredge, isochrysis tips to culture

Isochrysis can be a little tricky for some reason. I have pretty good luck with it, but some really struggle.

In my experience, Iso can be a little sensitive to strong light at times. I think the system the OP is using has fairly strong light. Might want to try reducing the light a little. I think Iso likes 35ppt salinity the best too. Some of the other species seem to do just as well at lower salinities, so might be worth double checking the salinity.
 
Isochrysis can be a little tricky for some reason. I have pretty good luck with it, but some really struggle.

In my experience, Iso can be a little sensitive to strong light at times. I think the system the OP is using has fairly strong light. Might want to try reducing the light a little. I think Iso likes 35ppt salinity the best too. Some of the other species seem to do just as well at lower salinities, so might be worth double checking the salinity.
Thanks! Really appreciate the advice.

Last week we tried a new approach and sterilized our salt water. Added bleach, let it sit for several hours, then neutralized it with sodium thiosulfate. It was only one culture but it was the BEST iso culture we've ever grown.

This week we ran the same approach with the saltwater and are going to try growing four cultures: nanno, tet, iso, and porph. See how it goes!
 
I use the Poseidon reef system too and do Nanno and tet. I haven't tried Iso, but what was mentioned for salinity would be a good thing to check. I'd also check how much starting F2 fertilizer you use, for whatever reason I feel that Tet gets to capacity quicker and consumes the nutrients fast.
 
I use the Poseidon reef system too and do Nanno and tet. I haven't tried Iso, but what was mentioned for salinity would be a good thing to check. I'd also check how much starting F2 fertilizer you use, for whatever reason I feel that Tet gets to capacity quicker and consumes the nutrients fast.
Our salinity is typically in the 34.5 - 35 range. That sound good for these species?

And just to be clear, are you suggesting we use extra F2 with Tet? What about nanno, iso, and porph?
 
Our salinity is typically in the 34.5 - 35 range. That sound good for these species?

And just to be clear, are you suggesting we use extra F2 with Tet? What about nanno, iso, and porph?
From my testing in the last 10 months of phyto growing, I actually found 1.022 to be best for Nanno and tet cultures. I also found from personal experience and reading that certain phyto strains are more sensitive and crash easier. Nanno definitely crashes easier than Tet, so using alcohol rubs and making sure everything is clean is important.

And yes, I use extra f2 with Tet.

Other experimenting I've done with the Poseidon reef system is the hours of lighting. I think everything states 16 hours for phyto culturing, but I always end up with "burn" like circles on their disposable bags when I ran 16 hours, so I've cut it to 12, then a break of an hour and then 2 more hours. This seems to work for me. I actually do my culture opposite from daylight timing so the light is on throughout the middle of the night since I also found that this will mitigate temperature swings since the lights heat up a lot and nighttime works best to not overheat the culture vessels. I experienced way less crashes doing this.
 
Kasrift made me think of something else. Iso is a little more sensitive to high temperatures than some species. If the culture temp gets much over 100 degrees, the culture could crash. I'm not sure if it is possible that the culture could reach that temp...
 
In my experience, Iso can be a little sensitive to strong light at times. I think the system the OP is using has fairly strong light. Might want to try reducing the light a little. I think Iso likes 35ppt salinity the best too. Some of the other species seem to do just as well at lower salinities, so might be worth double checking the salinity.

Have you found any websites that give information for each species? Light, size, salinity, temp, etc?

Also, for your cultures, do you put all the F2 in when you split and then leave it or do you monitor nutrient levels and add more as needed?
 
Last week we tried a new approach and sterilized our salt water. Added bleach, let it sit for several hours, then neutralized it with sodium thiosulfate. It was only one culture but it was the BEST iso culture we've ever grown.
Those of you who bleach, are you having to check chlorine levels each time you split a culture? Anyone worry about having too much sodium thiosulfate leftover after neutralizing? Just wondering how this might affect the water quality. Also, wouldn’t you have to sterilize the sodium thiosulfate? If so, weekly I’d assume?
 
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Have you found any websites that give information for each species? Light, size, salinity, temp, etc?

Also, for your cultures, do you put all the F2 in when you split and then leave it or do you monitor nutrient levels and add more as needed?

I don't really know of a website like that. I have pieced together info from various sites over time. Maybe I'll have to try to document some of it at some point.

Adding enough fertilizer to reach the plateau phase is probably best. Making standard F/2 concentration should work fairly well for most species. You can experiment and see if a little more or less works better for your conditions. In my case, I usually need to make it a little stronger.

Don't forget that when you split the culture, the fertilize is pretty much exhausted (or should be anyway). So, you need to add enough fertilizer for the total size of the new culture - the phyto plus the new saltwater.
 
Those of you who bleach, are you having to check chlorine levels each time you split a culture? Anyone worry about having too much sodium thiosulfate leftover after neutralizing? Just wondering how this might affect the water quality. Also, wouldn’t you have to sterilize the sodium thiosulfate? If so, weekly I’d assume?
Good question. I’d have to find the original calculator I came across but my understanding is you don’t have to be precise with the sodium thiosulfate. In fact it may be beneficial to go a little heavy handed with it…it will neutralize all the chlorine and is, in itself, relatively harmless to the tank inhabitants.

With relatively careful measurement all the chlorine should be neutralized and any excess sodium thiosulfate will be minimal. I believe the thiosulfate also breaks down somewhat quickly in the tank.
 
The concern was geared more towards the phyto culture than the tank itself, as the excess would likely be insignificant when added to the display. Seems like it’s not much of a concern though.
 
The concern was geared more towards the phyto culture than the tank itself, as the excess would likely be insignificant when added to the display. Seems like it’s not much of a concern though.
Ahhh gotcha.

So my wife is the one who does the phyto culturing. She says she doses the sodium thiosulfate, mixes the saltwater, and then waits 24 hours before starting the culture.

FWIW, this is this week’s culture. Started 4 days ago.

07AD9EC5-EB48-4AB4-829F-6B3585AC0A75.jpeg


From left to right it’s Tet, Porph, Nanno, and Iso.

Since starting the bleaching of saltwater, our Iso cultures have bee great.
 
Ahhh gotcha.

So my wife is the one who does the phyto culturing. She says she doses the sodium thiosulfate, mixes the saltwater, and then waits 24 hours before starting the culture.

FWIW, this is this week’s culture. Started 4 days ago.

07AD9EC5-EB48-4AB4-829F-6B3585AC0A75.jpeg


From left to right it’s Tet, Porph, Nanno, and Iso.

Since starting the bleaching of saltwater, our Iso cultures have bee great.
Nice. I did nanno, tet, and iso for awhile from a culture I got from Eldridge. The iso worked great for about 1-1.5 months, then it got contaminated. I was getting pretty sloppy towards the end, so not really all that surprised. I now just culture a single gallon of nanno culture and use UV for sterilization. Thinking about giving Iso another try, but still deciding if I want to sterilize more stuff each week lol.
IMG_4784.jpeg
 
Adding enough fertilizer to reach the plateau phase is probably best. Making standard F/2 concentration should work fairly well for most species. You can experiment and see if a little more or less works better for your conditions. In my case, I usually need to make it a little stronger.
Yeah I guess I'll have to figure this one out with trial and error. I can try to increase the dose over time to see what the max plateau density I can get without starting with such a high F/2 concentration to start with that it causes problems.

I was having a conversation on another thread about fertilizing the primary after a split. Others thought that you couldn't sterilize the water plus F/2 because the F/2 would be damage by the heat. How are you keeping the F/2 sterile?
 
Ahhh gotcha.

So my wife is the one who does the phyto culturing. She says she doses the sodium thiosulfate, mixes the saltwater, and then waits 24 hours before starting the culture.

FWIW, this is this week’s culture. Started 4 days ago.

07AD9EC5-EB48-4AB4-829F-6B3585AC0A75.jpeg


From left to right it’s Tet, Porph, Nanno, and Iso.

Since starting the bleaching of saltwater, our Iso cultures have bee great.

Looks good. What is the Porph? I don't think I am familiar with that species...
 
Yeah I guess I'll have to figure this one out with trial and error. I can try to increase the dose over time to see what the max plateau density I can get without starting with such a high F/2 concentration to start with that it causes problems.

I was having a conversation on another thread about fertilizing the primary after a split. Others thought that you couldn't sterilize the water plus F/2 because the F/2 would be damage by the heat. How are you keeping the F/2 sterile?

I am careful to keep the fertilizer clean and uncontaminated, but I use bleach to sterilize the saltwater and fertilizer. I think that heat probably would damage the vitamins in the fertilizer. When I have experimented with heat, it would crystalize some of the salt, so I never had luck using heat for sterilization of the medium.
 
Looks good. What is the Porph? I don't think I am familiar with that species...
Pretty isn't it? My wife found it and thought it would be a nice addition to the mix.

It's Porphyridium curentum. Apparently one of the only true red pigments in a microalgae. You can read about it HERE if you scroll down a bit.
 

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