Below is an instruction that describes a task. Write a response that appropriately completes the request in English. Please answer in English.

### Instruction:
John has a very inefficient toilet that uses 5 gallons of water per flush and his household flushed 15 times per day.  He replaced it with a toilet that uses 80% less water per flush.  How much water did John save in June?

### Response:
The old toilet used 5*15=<<5*15=75>>75 gallons of water per day.
There are 30 days in June and this toilet uses 75*30=<<30*75=2250>>2250 gallons a month.
The new toilet uses 5*.8=<<5*.8=4>>4 gallons less water per flush.
So, it only uses 5-4=<<5-4=1>>1 gallon per flush.
That means it only uses 1*15=<<1*15=15>>15 gallons per day.
All together, it used 15*30=<<15*30=450>>450 gallons in June.
So, he saved 2250-450=<<2250-450=1800>>1800 gallons per day.
#### 1800