Organic pH+ corrector with humic acids

Bio-Up can be used at every watering if needed, with all grow media and all the liquid fertilisers in the range, such as Bio-Grow or Bio-Bloom, whether you water by hand or run a hydroponic system. It can be combined with Bio-Down, its citric acid counterpart, to correct pH in either direction depending on the day's reading. In coco fibre, which barely buffers pH at all, this check goes with every batch you mix. In hydroponics, the pH of the sump tank shifts over the course of a few days as the plants take up nutrients, which is why regular monitoring makes more sense than a single adjustment when you fill the tank.

In open ground or in a compost rich in organic matter, soil life cushions pH variations, so corrections are needed less often than in soilless growing. This is where the absence of a strong acid matters most: Bio-Up raises the pH without harming the bacteria and fungi that break down organic matter and release nutrients. You can check the effect of your corrections by occasionally measuring the water that drains out from under the pot, which reflects the true condition of the root ball better than the water you pour in.

In an aquaponic system, the pH drops of its own accord. Nitrification, the work of the filter bacteria that convert the fish's ammonia into nitrate, consumes the water's alkalinity and produces acid. The target pH is also higher than in hydroponics, between 6.8 and 7.0, because the fish, the bacteria and the plants all have to be looked after; the tolerable range extends from 6.4 to 7.4. Below 6.4, correction is made with a mineral base added very slowly, over several days, such as calcium or potassium hydroxide, or potassium bicarbonate for aquaponics, which supplies potassium to the plants at the same time.

Bio-Up is dosed for irrigation water and nutrient solutions, not for water in which fish live, so you do not pour it into the pond. It does, however, have its place in a decoupled aquaponic system, where the fish water feeds a separate plant loop that does not return to the pond. In this loop, you can bring the solution down to 6.2 to 6.5, the range vegetables prefer, without touching the fish's pH. To monitor the pond's alkalinity, which must stay at no less than 100 mg/L expressed as calcium carbonate, a KH carbonate hardness test complements the pH reading, as the article regulating pH in an aquaponic system explains in detail.