Grow tent in shed in the gulf coast. Climate control is almost impossible.

First time poster. I have a 4x4 tent and 2x4 veg tent inside of an 8x16 shed. The shed has been insulated and mostly sealed. I have a 8k btu window unit and a 30 pint per day dehumidifier. I am an experienced grower for about 10 yrs but I have alway been fully indoors until this set up. this set up is more of a hybrid system with small amounts of air being taken from outside (through a filter) to provide co2 and fresh air. I use a 1k hps in the flowering tent and 2 300w leds in the veg tent. there seems to be very little condensation in the tents but outside of the tents I've noticed mildew and mold on tools and equipment inside the shed which prompted the purchase of the dehumidifier. I'm posting to see if anyone else who lives in a humid environment with daily rain/fog has a "hybrid" indoor/outdoor system that works for them and how they are able to maintain a healthy mold free environment for the grow. the dehumidifier dropped the humidity in my shed from 90% to 40% but I still have condensation on my duct work. should I insulate the ducts? I have my hps drawing outside air and venting it straight through to outside which hasn't been a problem. my tent is on a separate ducting system drawing ~50% outside (humid/cool) air and 50% a/c air from inside the shed. any advice or suggestion would be appreciated. I have a scrog soil grow with 3 plants in the 4x4 tent in 15g smart pots filled about 3/4 of the way. I usually can yield around 30-32oz with this set up in a fully indoor setup but I have moved and do not have the power capabilities to go fully indoor.

If the RH is really at 40% (meter is accurate) then I see nothing to worry about.

If its cold air going through a metal duct, condensation can occur at lower humidity levels. One can insulate the duct to prevent this.

I can easily insulate the ducts but I think my main question would be if it is beneficial to have the outdoor air/co2 coming in or if I should go for a completely sealed shed and supplement with co2. I can control temp and humidity now quite easily. I was growing with a completely sealed shed first and was yielding 24-26 oz. just venting the ~50% fresh air I’ve increased to 30-32oz. Does compressed co2 help enough to justify the cost and extra work? Or should I just insulate the ducts and continue without supplementing co2? During the summer months our outdoor temps are constantly in the high 90s so I cut off the hps and outside ventilation and run strictly leds but get a much lower yield(which is still more than enough) I just don’t want to waste my time/funds with a mold problem, the condensation this week has been unmanageable for the first time. It’s almost the same temp outside as inside but everything is sweating.

My yields went way up using CO2 and a good CO2 controller. Less venting = less odor outside the grow area if thats an issue for you.

Even in a sealed room id vent once every 24 hours for about 15 minutes to push out the ethelyene gas.

To avoid mold problems get a good humidity meter and watch that. Never let it above 50%.

Note that if room air cools but contains the same amount of water, the relative humidity rises.

Also, if venting the dehumidification is really fighting air your bringing in.