watering schedule tips for the baby hydro

Watering schedule

Every watering when using the reservoir is 5 minutes, the only thing you’ll change throughout the grow is the amount of times watering occurs. Expect to replace the reservoir once a week, I just take that water and stick in house or garden plants so it’s not a waste.

You can top off the reservoir as often as you like, it’s best to just use plain water till you get more familiar with the process. If you have PH and EC meters you can top back with nutes as well, if you’re comfortable doing it. 

A good starting point for EC from week 0-2 is around 1-2EC. From week 2-4, around 3EC. From week 4-7(ish) you can go all the way up around 4EC. In the last week or 2 of flower I‘ll drop it back down around 1EC.

PH range from 6-7 is good, I like to have it float around a bit versus trying to hit a static number all the time.

Temperature from 78-82 and RH from 55-60% You can run this every day. I don’t find high levels of Co2 to be beneficial so I run it 600ppm all the time. 

4 inch rockwool can hold roughly 24 ounces of water at full saturation.

A dry 4" cube, including the watering cap and enclosure weighs 187gr

Fully saturated, the weight is 867gr. 

24oz of water weighs approximately 680gr. If we wanted to calculate a 50% dry back, then we would subtract 1/2 of that 680gr of water which gives us 340gr. If we take the dry weight of 187gr and add it back to the 340 we get 527gr. If you use a food scale and your block, cap and container weighed 527gr, then you have achieved a 50% dry back. 

When starting out I don’t suggest setting up your reservoir until the plant needs to be watered at least once a day. I also don’t start adding h2o2 until I’m actually using the reservoir. You can expect to go anywhere from 2-3 weeks (if starting from seed) without using the reservoir. Starting from clone, you can expect to start using the reservoir sooner. 

When starting out it’s better to use a food scale to calculate the moisture percentage until the plant is established and using the reservoir. Familiarizing yourself with the weight of the block in hand is very useful going forward.

Once your plant is well established and using the reservoir, it’s going to need trellis sooner or later or it’s going to fall over. Once the plant is in a trellis, weighing the container is no longer an option so at that point you can start using the volume of water used per day to calculate moisture percentages. 

Even in the trellis you CAN still get a little lift on the block and see how light it feels. 

So for example, I like to be present for at least the first watering of the day. I start with a full reservoir and after that first watering, I’ll top it back off with plain water and count how many oz I used. 12oz would again be a 50% dry back. 

The math to calculate your % is simple. 

If we used 10oz we divide by 24 (100%) then multiply by 100. So that would be a 41.66% dryback. 

Another: 18oz used, divided by 24 is .75 times 100 is a 75% dryback

And one more just for fun: 7oz divided by 24 is .291 times 100 for a 29% dryback.

The higher the dryback % would be considered more generative vs a low dryback would be vegetative. I’ll say you can use 30-50% all the time if you’re starting out and adjust and tweak things from there. Most people would generally use a smaller dryback, but I’m not most people.

The first watering will always be when the lights turn on. Eventually you’ll add a second watering and that one I add somewhere in the middle of the day.  Once you’re up to around 3 watering per day, I add the last watering right when the lights turn off. Once you’re at this point, if adding or removing waterings, I divide them equally into the day period. So if you were watering 5x a day, that would be once at lights on, once at lights off and every 3 hours in between (for flower) 6x a day would be roughly every 2.5 hours and 7x a day would be every 2 hours, always keeping their first and last watering at lights on and lights off. 

You can also calculate the average per watering for the entire day. Simply take the total oz used for the day, divide by the number of waterings and then apply the same math we used for a single watering. 

Any questions? Dont hesitate to reach out!