The liquid ferts I use are Seachem flourish, iron and trace elements. Flourish tabs in the substrate. Deep Blue Solarmax T5 Double Strip both full day light and blue lights for 8 hours a day on a timer. Mostly sand substrate mixed with medium gravel. I use liquid ferts once a week as well.
When you say trace elements, what are you using?
When fertilizing your tank you want to dose with micro nutrients and macro nutrients.
Micro nutrients = trace elements
Macro nutrients = NPK nutrients
The seachem flourish is a micro nutrient supplement. So it is your trace elements.
Sounds to me like your lacking in macro/npk nutrients.
NPK = Nitrates/Potassium/Phosphate.
In most issues of deficiency of nutrients its the NPK that most lack. Besides lacking complete nutrients you also probably need to dose more then once a week. But rotate what you dose.
Also if you really want a better way and to save money. Ditch the liquid seachem ferts as the cost $$$ and switch to a dry fert. Way cheaper, very effective and will last you much much longer for the same dollar spent.
How often do you use the root tabs? Where do you place them? Could also recommend a better and less expensive tab.
Your light is one meant for reef it sounds like. The blue atinic bulb isnt the best plant growth light. Id recommend 6500K to 10000K bulbs.
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