Alternatives to sodium nitrate dosing now

[Enigma84]

Hi to you all.
I am from the UK and have used a 500g tub of sodium nitrate for the last 3-4 years to increase nitrate concentration when needed.
That tub did me well, but now it's running out and I need a replacement. Try as I may, none of the companies that offered this for sale are still selling it in the UK with the exception of on 500g tub for £70.
Now the obvious would be potassium nitrate or calcium nitrate but these are already at the top end of what I want, and I don't need to raise them anymore. Lowering them would be even better.
What are people using as an alternative to sodium, potassium or calcium nitrate to raise them?
I saw lithium nitrate which would be ideal, however it is super expensive. I have heard people talking about ammonium nitrate and sodium nitrite, however I don't want to cause any long term issues I don't need.
Your thoughts appreciated.
Ben

 

[BriDroid]

A lot of us have started to dose ammonium bicarbonate with great results. Do you have access to that? It may be a way to dose some N and some ammonia that the corals seem to love!

 

[Enigma84]

A lot of us have started to dose ammonium bicarbonate with great results. Do you have access to that? It may be a way to dose some N and some ammonia that the corals seem to love!

Ok, looks easy to get and cheap enough. Does it have much of an effect on alkalinity in comparison to the end result raising nitrate? You don't happen to have a link to any calculators on amount used versus resultant nitrate boost do you?
Much appreciated

 

[BriDroid]

Ok, looks easy to get and cheap enough. Does it have much of an effect on alkalinity in comparison to the end result raising nitrate? You don't happen to have a link to any calculators on amount used versus resultant nitrate boost do you?
Much appreciated

It does use up some KH for sure. I had to increase my All for Reef dose from 1.5ml to 2.0ml to keep it steady. My tank is very small though, about 8 gallons total volume. I'm no expert by far, if you haven't already, check out the thread from Randy on this topic. Lots of good info in there!
https://www.reef2reef.com/threads/diy-ammonia-dosing-for-low-nitrate-systems.987087/