kevin24018
Designing your
hydroponic system is all about designing it for the plants your growing. Using buckets to grow lettuce in a water culture system will work, but not the best use of space and water volume. You'll want something short and wide to make the best use of space without wasting water volume. Again here is where knowing how many plants, and what variety you want to grow makes a big difference in the design. As an example: butter crunch grows low, and Roman grows tall and can get top heavy. Neither require the water depth of more than 4-6 inches. So knowing what is going to be growing in it, and how many plants will be in it is essential to designing a good working hydroponic system.
As for temperatures, Most verities of lettuce prefer cool weather (below 80 F). But if you look around you can find some more heat tolerant varieties. Regardless of what plants you want to grow you'll still want to make sure your water/
nutrient temperatures are within range. Water/nutrient temps that are to high will cause heat stress as well as other issues, and water temps to low will stunt plant growth. I wrote this article
Nutrient Solution Temperature is Important, and it includes every method I know of for cooling your nutrient solution.
What are the average day and night time temperatures in your area now, and for the next 4 months. Avoid using artificial lighting as much as you can because it costs money not only to buy the
lights, but in electricity to run them as well. So if you can use natural sunlight to grow your plants, it's a lot more economical to grow them.
P.S.
You don't need to use food grade plastics unless your trying to grow certified organic produce. I like to use short storage totes like this:
Expandable Hydroponic Water Culture System to grow lettuce. I built that system for about $25.