It has been a few weeks since i last posted and most agreed that i needed to lower my light period and WPG. I did, clipped out all bba, stocked the tank with about 3x as many plants and got my co2 to a better level. I find that most of the plants are pearling regularly and the bba is not returning. I do ramp the lights for two hours in the middle of the day and the tank explodes with pearling even the HC when the extra light is on. Is it safe to say that i can extend this 4wpg photo period for half the day?

Thanks

The more light you have, the more critical everything else is. So, if you ramp up the light for 4 hours you would have to be very sure you had plenty of CO2, dispersed well throughout the tank with good water circulation everywhere in the tank, plenty of all of the other nutrients, good water cleanliness, no big accumulation of rotting debris on the substrate, etc. And, as this succeeds in driving much faster plant growth, you would have to be pruning a lot more often to avoid the overly thick plant growth stopping the water circulation. Otherwise, the algae will take the opportunity to start growing again.

What would be your goal in increasing the high light period?

growing in the tank at a better rate. I have a good load of plants but i want the tank to look more filled in, so if they grow faster ill have a better chance at trimming and replanting.

If things are in proper balance, light, nutes, co2, etc you will soon have your wish. Plants will take a couple of weeks after being stressed to start growing optimally again.

Many stem plants can grow 3" and more a week easily. You will soon get tired of trimming regularly.

Try keeping what you have for another 4-8 weeks and see how that goes.

Great advice on patience!!

one other question. does substrate get old to the point where you need to toss it and start again? I have had my eco complete for a year + now, Do the nutrients get depleted to a point that one has to refil the tank with new stuff?

You can grow plants very well using an inert substrate and relying on water column fertilizing for the plants. That means you don't have to replace any substrate just because it runs out of some nutrients. But, you will have to gradually shift over to full water column dosing. Or: you can do as Tom suggests, and use a nutrient loaded substrate, like Aquasoil, but do full water column dosing from the beginning. That lets the substrate nutrients last a lot longer and act as a back up source of nutrients for the plants when you neglect to dose the water for a few days.

Amen!!! Trust me, be careful what you wish for!