problem with tomatoes

i seem to have a problem with my toms ,and i was wondering is it blight , am a bit of a newbie at this to be fair tho

 

What are they growing in? Pot, Grow bag, or Outside?

What are you feeding them? and How often?

 

once a week with water from the pond , maybe the problem?????? and a tomatoe feed (shop bought )

 

the pond water is not the problem , you need to keep the compost moist at all times as the young feeders roots will dry out and can not take up the calcium it will sort it self out quickly , we have another post on here about the same problem , I suggest water the plants with "epsom salts" table spoon in a watering can will help speed it up for you

Spruce

 

Probably not often enough. If growing in containers them once a day more likely and, if it pots in a greenhouse, then probably twice a day in hot weather.