I just finished my hydroponic garden with 18 tomato plants in 5 gallon buckets, using a 41 gallon marine cooler for the nutrients, a 500 gph water pump, an air pump to add oxygen to the water. Tomato plants growing in perlite after washing off potting mix.
I didn't have heat issues with the dark color buckets, i did however notice as the tomato plants get bigger they are getting more thirsty, the past few days i mixed an additional 15 gallons of nutrients. the tomato plants are looking like little trees, the stems are quite thick. It is beginning to look like the hydroponic tomato plants are going to grow bigger and taller then my other 20+ automatic rain water tomato plants.
Perlite is a great growing medium, I use it sometimes too.
It's great for root development, especially for seedlings.
Do you have air stones in each bucket or just in the res?
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