Fish Tank Cleaner Tube

whats this weird white stuff in my fish tank ?

There’s this weird layer of white stuff on the top of my fish tank and on the air tubes but its above the water and when ever i touch it or pink it off it crumbles into some sort of powder. I have had this for a while and i’ve just been cleaning it off but now its starting to come to the outside of the lid .

What is this and how can I get rid of it?

Sounds like limescale and is cause by the minerals in hard water. Do you get a build up in your kitchen kettle?
You can scrape it off or wipe it off if not too hard.

10 Gallon Aquarium Freshwater Cleaning Demo

TERAPUMP (TM) TRHD01F Battery Operated Liquid Filter / Transfer Pump $14.99 The filter has many uses including protecting the working parts inside the pump from debris, which have been known to cause damage or even completely stop transfer pumps from working. The Liquid Transfer Pump with FILTER ATTACHED is battery operated & uses only 2 D batteries (not included). You can pump 7-8 quarts of liquid per minute. Just push the button on top of the liquid transfer pump to be…