Ph and fertilizers

PH is likely to have a significant impact on the nutrient solution. A rating of 6.7 - 6.2 is the optimal level to make certain there isn't any nutrient lock up. A hydroponic set-up is likely to require the right PH level to match the soil prior to planting. PH is likely to go down with the presence of phosphoresic acid. Potash or lime is able to increase so the ideal acid is present. Invest in one of the inexpensive PH metres to check the hydroponic medium, water, and soil to ensure you aren't seeing acid or alkaline issue over time. A lot of the neutral soil is likely to feature a minimal amount of vinegar to ensure that they are able to stabilise in the region of 6.5 – 7 PH. 

A higher proportion of fertilisers can cause the PH rating in the soil to change. Including a fertiliser in the medium is certain to mean a higher reading in relation to acidic PH. 

Over time the total salt in the soil, which is produced by the fertilisers breaking down, is likely to cause the medium to become that much more acidic and at a certain point the salt is going to limit the growth potential for the plant life. In addition, as the plant develops over time the roots aren't as effective at providing sufficient food for the leaves. In an attempt to slow the build-up of salt in the medium and to maintain a healthier growth area it is likely to benefit if you are able to start feeding the leaves at the 1 1/2 month stage. A fertiliser mixture can be combined with water and sprayed directly onto the leaves. The foliage is able to absorb all of the benefits that the fertiliser is able to offer. It might also benefit to use a soil fertiliser but make certain to avoid overdosing on the plants.