man i would seriously consider using soil and organic nutes. i use a 50/50 mix of Roots Organics and Fox Farms Happy Frog, but either of these alone will work well too. I don't recommend Ocean Forest especially if you want to grow blueberry, though a lot of ppl like it. I think it's too strong. Either way, organics nutes are much cheaper to use because they last a very long time, it's a lot harder to burn your plants and the taste is fantastic. I would say do that and get a few harvests before committing to hydro.
If you decide to stick with it, definitely get some easier strains in to really get down managing PH and PPM, etc. You should also probably try to find a different bucket. If i'm correct that looks like a Homp Depot bucket, which are not light proof. You do NOT want light in that res, as stuff will grow. sometimes walmart carries black buckets and they are great. Lowe's buckets are also light proof and i use those with success (the grey ones).
One more thing, you might try keeping the water level lower. i use almost the same exact setup, with a more beefed up airpump/stone, and i fill my buckets half way, sometimes just 1/3 full. Later on this will take more changing but it's worth it for the root health. You need to make sure the airstone creates enough bubbles, but this will act more like aeroponics than DWC, and is wonderfully efficient for the ease of operation.