So I asked AI your original question to see if I was explaining it right and if it could explain it better this is what AI said
It sounds like you're facing a combination of issues, but let's break them down step by step to get a clearer picture of what's happening.
EC Build-Up and Salts
The EC (electrical conductivity) meter measures the total concentration of salts (nutrients) in your solution. When you're seeing your EC rise from 1.7 to 3.5–4 as your reservoir gets used up, it suggests that the plants are taking up water but not the nutrients in proportion, which causes the salt concentration to increase. This is quite common, especially in systems like hydroponics or coco with drip feed, as the plants take up more water than they do nutrients.
As for the EC meter reading mainly "salts," it's important to remember that it doesn’t differentiate between good and bad salts. High EC doesn't necessarily mean it's only salts the plants need; it can also reflect an excess of certain nutrients that may cause issues.
Nutrient Lockout
While high EC can indeed contribute to nutrient lockout, it doesn't always happen in the way you might think. Nutrient lockout occurs when certain elements (like calcium, magnesium, or potassium) are present in excess or are out of balance, preventing plants from absorbing other essential nutrients. However, a straight-up EC of 3.5–4 isn't necessarily a direct cause of lockout, but it's definitely high, and could indicate that your nutrient mix is out of balance or that the plants are overwhelmed by salts.
Problems with Bud Size and Growth
If the buds have stopped growing since week 5, it's possible that nutrient uptake has been impaired. Too much salt in the root zone can hinder the plant's ability to take in necessary elements like phosphorus, potassium, or calcium, all of which are vital for flower development. Here's a breakdown of potential issues:
- High EC (Salt Build-Up): When the EC is high in your reservoir, it means that salts are accumulating. High salt concentrations can cause osmotic pressure changes that make it harder for roots to take up water and nutrients, even if they're present. This can stunt growth, particularly in later flowering stages when the plant requires more phosphorus and potassium to develop buds.
- Nutrient Imbalance: Since your soil meter shows high levels of phosphorus (P) and potassium (K), it might indicate that the plants are getting more of these elements than they can absorb. A build-up of excess nutrients can cause toxicity or lockout of other critical nutrients like nitrogen or calcium, leading to poor growth.
- pH Imbalance: If you're not adjusting your pH regularly, it could be affecting nutrient uptake as well. In coco, the pH should typically range between 5.8 to 6.2, as this is the optimal range for nutrient absorption. A pH outside of this range could make certain nutrients less available to the plant, further contributing to nutrient deficiencies.
Potential Causes and Solutions:
- Flush the System: A good practice when EC gets too high is to flush the system with plain water (pH-balanced) to reset the environment. This will help reduce excess salts in the substrate and lower EC. After flushing, you can feed with a lower EC solution to gradually bring the plants back to an optimal range.
- Adjust Nutrient Ratios: Ensure that your nutrient mix is balanced for the flowering stage. High phosphorus and potassium can be good, but if you're in the 6th week of flower, the plants still need enough nitrogen, calcium, and magnesium. Too much K and P can inhibit calcium uptake, which may lead to deficiencies.
- Monitor pH and EC Regularly: Continue checking both EC and pH regularly. For coco, your EC should generally stay between 1.2 and 2.2 during the early and mid-flowering stages. At the end of flowering, you can push the EC higher, but excessive EC can stress the plants.
- Watering Strategy: If you're seeing a high EC build-up, consider watering the plants more frequently but with a smaller volume of nutrient solution each time. This can help prevent salt build-up in the substrate. You might also want to top up the reservoir with just water, to help balance the salt concentration.
- Check for Root Issues: Over time, high salt concentration can lead to root damage or poor root function. Make sure your roots are healthy—look for any signs of root rot or discoloration. If roots are affected, a root-zone cleaner or a light hydrogen peroxide solution can help.
Understanding the Salt Effect
Excessive salts in the root zone can indeed create a kind of "nutrient lockout" by altering the osmotic balance and preventing water from being properly absorbed by the roots. However, lockout also tends to occur when there's a mismatch between nutrient ratios, where the plant cannot efficiently use the available nutrients due to competition for uptake.
In your case, the main problem seems to be an accumulation of salts, especially with high EC in the reservoir, which might be inhibiting nutrient uptake. When this happens, the plants stop growing and start showing symptoms of nutrient deficiencies, even though there's a lot of phosphorus and potassium available in the medium.
Final Thoughts
It looks like your EC might be too high, and this is likely contributing to the reduced bud size and overall slow growth. By flushing the system to lower the salt concentration and adjusting the nutrient mix, you should be able to get your plants back on track.
If you have any more specific details, like the pH levels or if you’ve noticed other symptoms on the plants (e.g., leaf color change, yellowing, or curling), that could help further refine the advice.
