Silicate dosing to combat dinoflagellates

[RobertK]

I have recently started dosing 40% sodium silicate as part of an ongoing effort against Amphidinium and Ostreopsis dinoflagellates in my tank. I've read as much as I can on this subject and it seems that maintaining a silicate level of 1-2 ppm is a reasonable target range. I bought a Hanna silica checker, which has an upper detection limit of 2 ppm (as SiO2). I started with the dose in Miami Reef's dosing chart and it got me to the middle of that range, but it was below 1 ppm the next day and completely depleted back to the baseline level (~0.2 ppm) in 2 days. So it appears I need to dose it daily or every other day to keep it in that range. Does that sound right? Thank you!

 

[Dan_P]

I have recently started dosing 40% sodium silicate as part of an ongoing effort against Amphidinium and Ostreopsis dinoflagellates in my tank. I've read as much as I can on this subject and it seems that maintaining a silicate level of 1-2 ppm is a reasonable target range. I bought a Hanna silica checker, which has an upper detection limit of 2 ppm (as SiO2). I started with the dose in Miami Reef's dosing chart and it got me to the middle of that range, but it was below 1 ppm the next day and completely depleted back to the baseline level (~0.2 ppm) in 2 days. So it appears I need to dose it daily or every other day to keep it in that range. Does that sound right? Thank you!

Seems like a reasonable conclusion

 

[Randy Holmes-Farley Verified Community Expert]

Diatoms, which are the reason to add silicate in relation to dinos, rapidly deplete added silicate. :)

 

[RobertK]

Diatoms, which are the reason to add silicate in relation to dinos, rapidly deplete added silicate. :)

Yes I am seeing evidence of that! I posted this because I saw it recommended in a couple of places to dose silicate weekly, but it appears more frequent dosing is required to maintain a level >1 ppm.

 

[Randy Holmes-Farley Verified Community Expert]

Yes I am seeing evidence of that! I posted this because I saw it recommended in a couple of places to dose silicate weekly, but it appears more frequent dosing is required to maintain a level >1 ppm.

Yes, I found that it rapidly depleted. Maintaining a specific level is not the goal. Diatom growth is, so dosing is needed, but not a specific maintenance level.

 

[RobertK]

Yes, I found that it rapidly depleted. Maintaining a specific level is not the goal. Diatom growth is, so dosing is needed, but not a specific maintenance level.

Yes but if we are trying to accelerate diatom growth above what occurs at baseline silicate level (0.15-0.2 ppm in my tank according to Hanna) don't we want to maintain a level greater than baseline?

 

[Randy Holmes-Farley Verified Community Expert]

Yes but if we are trying to accelerate diatom growth above what occurs at baseline silicate level (0.15-0.2 ppm in my tank according to Hanna) don't we want to maintain a level greater than baseline?

I don’t know what baseline really means. I expect silicate will deplete below reliable levels of detection as diatoms consume it. But I’m not saying it is not worth dosing repeatedly. In my old tank I dosed silicate once or twice a weeks for years to supply sponges.

 

[RobertK]

I don’t know what baseline really means. I expect silicate will deplete below reliable levels of detection as diatoms consume it. But I’m not saying it is not worth dosing repeatedly. In my old tank I dosed silicate once or twice a weeks for years to supply sponges.

In this case baseline means the silicate level before I started dosing.

 

[Randy Holmes-Farley Verified Community Expert]

In this case baseline means the silicate level before I started dosing.

I understand, but I’m not sure it is real. In any case, I assume it is used fast, and that, while ok to keep dosing, is not necessary to maintain that level constantly.

 

[RobertK]

I understand, but I’m not sure it is real. In any case, I assume it is used fast, and that, while ok to keep dosing, is not necessary to maintain that level constantly.

OK, thanks Randy!