VEVOR DWC Hydroponic System, 5 Gallon 8 Buckets, Deep Water Culture Growing Bucket, Hydroponics Grow Kit with Pump, Air Stone and Water Level Device, for Indoor/Outdoor Leafy Vegetables

Yes, tomatoes can be grown in it.

Here is the link to the manual: https://d2v0huudrf11kh.cloudfront.net/1622546333299%E5%BE%AE%E4%BF%A1%E5%9B%BE%E7%89%87_20210601173008.png

It is dwc.

We do not sell parts separately. All our products have a 12 month warranty and if there is a problem with your purchase during the warranty period, we will send you a replacement part free of charge(Except for consumables, they need to be purchased by you yourself). Please click the following link to contact us: https://www.vevor.com/pages/contact-us.

No, they aren't food safe.