my plant is in bad condition new leaves are very weak

Looking at the plants and the nurtients your feeding them, in my opinion your using too little. After week 4 flowering Bio grow should no longer be used. The plant is focusing on the buds and not on new leaf or stem growth. The lower leaves will start to turn yellow becuase the plant is feeding off them. its normal. also Bio heaven - Bio bloom and top max you are using too litte. For every 2 liters of water should be 8ml. Also the first thing i notice is the plugs sockets. keep them out of the grow tent. i hope this helps.

Hello dear, reduce the fertilizers containing Nitrogen and do a rinse

Your feed is extremely heavy in nitrogen, and in flowering the plant does not need much nitrogen. Flowering npk ratio is 1-2-3. Potassium and phosphorus is main nutrition they want now.

Rule number 1 - LESS IS MORE. You are on verge of Nitrogen toxicity or already have it. Some bottom leaves can fade a bit, because of lack air, light and so on. Rule number 2. No FLUSH for soil growers if you want to avoid other problems, while you correct first ... Ph 6,3 always , no matter you feed or go plain water. Watering only when pots are light. Have good cycle of wet/dry. 2x cycles of wet/dry with plain water( no food indide), it should take you 7-10 days, then you can return to feeding schedule. Till week 5-6 of flower they still need Nitrogen, just put less. Now they are in flower, so with next FEEDING ( not watering) you should adjust your formula and add flower/bloom nutrients too. All the Best ! Garden looks nice, all should be diamond ! Dont stress ;))))

Pienso que debes de hacer un lavado de raices para descartar la sobrealimentación y luego ir añadiendo poco a poco los fertilizantes