I laid my turf a week ago and I\'m watering it twice daily as its quite warm but it still looks like in certain spots it\'s dying so please somebody help me
Unfortunately, laying anything during the more extreme parts of the year can yield results like this. Watering will be a very delicate balance. You want the roots to remain slightly moist, but do not want them wet. This invites rot and root suffocation.
By autumn, you will likely know what repair needs to be done. Until then, offering proper moisture content, and letting it dry very slightly between watering will be necessary. Adding shade cloths in those spots may help, if you feel that this could be sun related.
https://www.gardeningknowhow.com/lawn-care/lgen/brown-lawn-fixes.htm
https://www.gardeningknowhow.com/lawn-care/lgen/fixes-for-yellow-lawns.htm
https://www.gardeningknowhow.com/lawn-care/lgen/treating-lawn-diseases.htm
Not artificial grass
There are many options that alternatives to grasses, but there are a few lawns that will stand up to this traffic. Here are some articles to help:
https://www.gardeningknowhow.com/lawn-care/lawn-substitutes/lagen/high-traffic-lawn-options.htm
https://www.gardeningknowhow.com/lawn-care/lawn-substitutes/lagen
I have had sod installed twice and it keeps on dying. I have an irrigation system so it does get watered. The topsoil has vanished and what remains is mostly sand. Is there a type of grass that does well growing in sand?
You do have a few options, actually! These articles will help:
https://www.gardeningknowhow.com/ornamental/foliage/ornamental-grass/ornamental-grass-for-sand.htm
https://www.gardeningknowhow.com/ornamental/foliage/beachgrass/american-beachgrass-care.htm
https://www.gardeningknowhow.com/lawn-care/sandy-soil-lawns.htm
How the best height of Mower?
Generally, this will be about 2 1/2 inches, leaving it a little longer at 3 inches during the heat of summer.
https://www.gardeningknowhow.com/lawn-care/lgen/lawn-mowing-tips.htm
It's quite a large area and I've hand cleared it 3 times already but they keep on coming up.
Yes, I would start to spray so that it will, at least, be more manageable for your new grass to emerge. Products containing the chemical, Glyphosate, are fast acting (within a week) and breaks down on contact with soil through a process called microbial degradation.
This collection of articles will help:
only need to know how to test my lawn PH level
We don't recommend brands, but you can find pH test kits at garden centers and plant nurseries. Your local extension service also will provide testing.
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/soil-ph-plants.htm
https://www.gardeningknowhow.com/garden-how-to/info/what-is-extension-service.htm