Al B. Fuct
once had a dog named
CG, you're right, knowing where to stop can be tricky. There's a bell-curve to this- not enough, just right and dead.
The trick with nutes is to use enough to get plants without deficiencies but not so much as to produce nute burns. Once you pass the peak of your bell curve, more nutrients will cause a reduction in growth.
If you like, you can grow a few plants at the same time that you give nutes of differing strengths to, perhaps 200ppm between each sample, and see for yourself which produces burns or deficiencies, etc. Bear in mind that before doing such testing, all other conds in the op have to be spot on so you are sure that when you see some symptom in the plants, you can be sure it is caused by the difference in nute strength as opposed to something like excessive air temp, for example.
800ppm does sound a bit low, though. I run my tanks at 1400.
The trick with nutes is to use enough to get plants without deficiencies but not so much as to produce nute burns. Once you pass the peak of your bell curve, more nutrients will cause a reduction in growth.
If you like, you can grow a few plants at the same time that you give nutes of differing strengths to, perhaps 200ppm between each sample, and see for yourself which produces burns or deficiencies, etc. Bear in mind that before doing such testing, all other conds in the op have to be spot on so you are sure that when you see some symptom in the plants, you can be sure it is caused by the difference in nute strength as opposed to something like excessive air temp, for example.
800ppm does sound a bit low, though. I run my tanks at 1400.