The Government had brought in the concept of TDS, through which persons are required to deduct TDS and deposit the same with the Government. Know more about TDS on fees for professional and technical services here
Portable pH/Dissolved Oxygen Meter DO Meter for Water treatment/Pond water and aquarium DO-9100 Supplier's reply: Hi,Denis,thanks for your kindly feedback,Hope we can have more cooperation in the future! Satisfied with this product too Online Wifi 8 in 1 PH TDS EC ORP Salinity Temperature ...