Tank base

[Barkas]

hi All. Im gona lay a 4 sq metre, 6 inch thick concrete pad onto soil, its a base on which to sit my new bunded 1000 litre heating oil tank. Should I add any additives the the mix, and should I lay anything on the soil before concreting like plastic sheeting , gravel or steel netting to strengthen the base? Sorry, posted in wrong section but I cant move it.
Thanks in anticipation

 

[PrenticeBoyofDerry]

If it's a soil base, dig a little deeper and get some in-fill before pour also sheet up over in-fill only to prevent moisture loss of mix.
Additives for ease of pour: Plasticizer with frost protection.

 

[HERTS P&D]

Also put in some 'road mesh' to hold it all together.

Andy