Is this a usable source of Potassium Sulphate?

[illumnae]

I'm located in Singapore and it's hard for me to find dry salts to use to fertilize my tank - my tank is about 2500 litres total volume, so using commercial branded AIO fertilizers (which is what I was doing until advised against if here) costs alot. I've resorted to looking across the border to Malaysia to source for what's hard to find locally and came across this Potassium Sulphate product (this is the same seller that I bought my Rexolin APN from). However what concerns me is that the description states that the Potassium Sulphate, rather than being K2SO4, is described as being 50% K2O and 18% S. Would this be an issue in mixing up my own AIO or should I look for another source?

This is the product: BM Behn Meyer Fruitka Soluble Potassium Sulphate (SOP) 25kg Kluang, Johor Bahru (JB), Malaysia Supplier, Dealer, Distributor, Specialist | Swee Chiang Hardware Sdn Bhd

This is an alternative that I found, would this be safer: POTASSIUM SULPHATE 500G SUPPLEMENT OF POTASSIUM & SULPHUR | Lazada Singapore

 

[John q]

K2SO4, is described as being 50% K2O and 18% S.

That's pretty much the standard content of K2SO4. Looks fine to me.

 

[illumnae]

That's pretty much the standard content of K2SO4. Looks fine to me.

Great thanks! I was concerned that it was a physical mix of Potassium Oxide and Sulphur particles and not actual Potassium Sulphate crystals

Would it be the same for a Calcium Nitrate product that said it contained Nitrogen and Calcium Oxide?

 

[tiger15]

The fertilizer trade has standardized labeling of ingredients in equivalent nutrient values, not necessarily related to the chemicals of origin. For example, potassium is always labeled as potash (K2O) equivalent, where the chemical is typically derived from potassium sulfate.

Check this SeaChem root tab ingredients labelling . Seachem - Flourish Tabs

 

[John q]

Would it be the same for a Calcium Nitrate product that said it contained Nitrogen and Calcium Oxide?

Yes, calcium nitrate usually contains N and Calcium Oxide. The nitrate side is generally No3 and a small percentage of NH4.

 

[illumnae]

Thank you! This is very helpful new information for me