Planted Tank Supplements in Saltwater (Seachem)

Hermie · Mar 30, 2019

Hi, I have a bunch of FW Seachem supplements leftover that I don't use, but I was wondering if any of these "ingredients" would be helpful for Macroalgae (ie: there might be something limited in my system and adding this would most likely help the algae).
Thanks!!

(Fe) Ferrous Gluconate (Flourish Iron)
(N) and (K2O) Potassium Nitrate, or urea (Flourish Nitrogen)
(P2O5) Potassium phosphate (Flourish Phosphorus) and (K2O)
(K2O) Potassium sulfate (Flourish Potassium)

LIreefguy · Mar 30, 2019

I used the iron one left over on my salt water reef. I put like 2 caps full in 600 gallons of water. It killed my yellow tang and caused stress on several other fish. It also turned my water tea color
So I wouldn’t use them.

Waters · Mar 30, 2019

NotASpammerDude said:
Hi, I have a bunch of FW Seachem supplements leftover that I don't use, but I was wondering if any of these "ingredients" would be helpful for Macroalgae (ie: there might be something limited in my system and adding this would most likely help the algae).
Thanks!!

(Fe) Ferrous Gluconate (Flourish Iron)

(N) and (K2O) Potassium Nitrate, or urea (Flourish Nitrogen)

(P2O5) Potassium phosphate (Flourish Phosphorus) and (K2O)

(K2O) Potassium sulfate (Flourish Potassium)

I don't know about the liquid supplements, but I use Potassium Nitrate (leftover from planted tanks) in powder form as an occasional supplement to raise nitrates.

Hermie · Mar 30, 2019

Waters said:
I don't know about the liquid supplements, but I use Potassium Nitrate (leftover from planted tanks) in powder form as an occasional supplement to raise nitrates.

do you think the potassium can hurt the corals?

Randy Holmes-Farley · Mar 30, 2019

NotASpammerDude said:
do you think the potassium can hurt the corals?

Seawater has a lot of potassium in it already. The boost will be small unless you use a lot of it.

These are all probably OK, but my main concern is how pure these are, which is more of a concern in seawater than fresh.

I'm not a fan of dosing urea as you cannot measure it.

Also, be careful as the ingredients are not what you list. K2O is a unit of measure of potassium, not an actual chemical that would be there (which, if so, would be a very high pH alkalinity supplement). Same for P2O5. it is definitely not present in the additive.