@@greenpinky, Not sure I am the right person to seek advice from. This is only my 4th grow.
I can't give you any information regarding the t5 lights, I've only ever used led.
I saw you mention you are growing in a soilless medium, but not giving nutrients. I might be wrong, but shouldn't you be supplying nutrients from the start if you are not growing in soil? Since there is either none or very little nutrients in something like coco choir.
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