Which trace elements does chaeto deppete?

[KGV]

Is there any literature about this? What is your own experience and does it suffice to perform water changes to replenish depleted trace elements or do you dose them?

 

[Doctorgori]

I wish there was a lil more info but there are many macro algae books that could offer better insight…
BTW iron is the my 1st thought but I’ll defer to better opinion
…I use brightwells chaeto grow, willy nilly I might add

 

[Betex]

I know with ReefMoonshine we dose extra Iron, Cobalt, Chromium and Manganese if you have Chaeto and I know mine grows like crazy and I started dosing these.

 

[hart24601]

I found my awc was not enough to compensate for chaeto growth but I have a large basement sump and a lot of chaeto compared to display.

I don’t know what elements it was lacking (plenty of po4 and nitrate in tank) but was melting away. Added 2ml chaetogro a day never had the issue ago. So while I can’t say exactly, for my system it was an ingredient in chaetogro that awc of IO or TMP didn’t supplement enough

 

[Subsea]

When I grew Red Ogo, Gracilaria Parvispora, for culinary sales to restaurant, I had it analyzed by a regional agriculture lab:

N @ 2.59%
P @ 0.082%
K @ 13.54%
Ca @ 0.555%
Mg @ 1.163%
S @ 4.81%
Zn @ 139 ppm
Fe @ 107 ppm
Mn @ 20 ppm
Cu @ 7 ppm

Make up water came from Trinity Aquifier at 1000’. Water analysis showed zero Cu & Zn with lowest detection limit at .001 ppm.

This water analysis proved to me that algae is a sponge and will absorb whatever is in the water. Unfortunately, the sulfur concentration in Red Ogo ruined the taste of the fresh seaweed.

 

[hart24601]

When I grew Red Ogo, Gracilaria Parvispora, for culinary sales to restaurant, I had it analyzed by a regional agriculture lab:

N @ 2.59%
P @ 0.082%
K @ 13.54%
Ca @ 0.555%
Mg @ 1.163%
S @ 4.81%
Zn @ 139 ppm
Fe @ 107 ppm
Mn @ 20 ppm
Cu @ 7 ppm

Make up water came from Trinity Aquifier at 1000’. Water analysis showed zero Cu & Zn with lowest detection limit at .001 ppm.

This water analysis proved to me that algae is a sponge and will absorb whatever is in the water. Unfortunately, the sulfur concentration in Red Ogo ruined the taste of the fresh seaweed.

The interesting question there is what elements are needed in what amounts vs what it absorbed due to availability

 

[jda]

I have been growing massive amounts of chaeto for more than a decade and iron is the only thing that I need to dose beyond mostly regular water changes.

 

[Randy Holmes-Farley Verified Community Expert]

Macroalgae takes up lots of trace elements (the answer is known for many species and is far more than they need to grow), but any given species certainly needs many of those to grow. Iron and manganese are two of the prime ones, but there are many more.

Other processes that you do not see also take up of trace elements, and at the end of the day, it doesn't so much matter what they take up as what they need added back to grow optimally. That answer depends on many factors, from foods fed to exports to inorganic minerals present in the aquarium (like sand and rock, etc.).