Healthy plants but low yields

biggest single factor for yield is light intensity. at some point, growing a plant bigger under the same light will not increase yield. it'll merely spread it out more... potentially to the point of vast majority turning out as larf. if the plant was relatively healthy, you can shelve concerns about your nutes. don't irrigate with a specific volum of water... irrigate until you get some runoff. if consistent about the poin t at which you do that, it will be a consistent volume, but not one you pick out of a hat. time between? depends on how fast the plants are drinking... so, it should be based on weight or top 1" deep is dry in soil. coco you want to repeat when color up top changes, so a bit sooner than soil. this could be genetics.. this could be the light relative to size of plant grown under it. many light manufacturers lie on teh spec sheet... not gloss over but outright lies and bullshit. In general, the cheaper they are, the more they lie through their teeth. lately, it looks like the mid-level stuff from typical vendors like spider farmer, mars and vipar are a bit more accurate than they used to be. if you brush up on the math, you can easily pick the honest ones out by comparing to real specheets from original manuacturer of a particular diode used. umol/s of photons and area of coverage (relative to 1m^2)... this is used to calculate PPFD. based on number of hours per day you have lights on, this can calculate DLI. if DLI is at or near 20ish, it's going to be a small yield. If near 40ish, you are pushing limits of ambient CO2 and likely a bit beyond if you don't control RH and temp too. If up near 40, it's genetics or some other issue holdingn it back. autos vs photos will matter... you have to provide 50% more light over 12 hours to match what you provide over 18, for example. umol/s, area of coverage and how long it is one = DLI. if your DLI is low, this is likely why. (refer to a DLI chart after you calculated what your lights provide. assumes they give some accurate specifications.