Black tubing works fine. Algae can't grow without light so opaque tubing solves the problem.
You can't use a standpipe without a dribble hole. You'll end up with standing water and the growth won't do as well.
Here's a picture of the test setup of my flood and drain system and the proven setup used for cleaning the guppy tank. Nothing is fastened permanently. I have rubber bulkhead fittings which allow me to draw the tubing out of the fittings if I have to disassemble the system. These work well in the fairly thick wall of the pipe.
Flood and drain trial
Here are the things I learned.
The drain stand tube must be clear of all grow medium and exposed to light. This prevents the plants from overcoming the stand pipe and choking off the water flow. It also prevents the medium from washing out of one bed into the next and ultimately into your fish tank. I have a temporary dam installed at the stand tube end 2" short of the stand tube. This lets me visually check the dribble holes to ensure they stay free from blockage. If the water flow isn't correctly adjusted it will make surge/gurgle noises. This is only an issue if the noise bothers you. Adjusting the in-flow solves this problem.
The top of my stand pipe end is cut at an angle. I'm sure I had a reason for this but it doesn't instantly come to mind.
The grow medium MUST be ph neutral. Anything else cannot be moderated, causes plant damage, inhibits growth and causes damage to the fish. When you start up the system make SURE you check ph frequently. I use oyster shell to moderate the ph until it settles and if left in the system does no damage. I line the bottom of the plant bed with oyster shell before adding the plants and then the media. Oyster shell is not a universal fix. The ph of our water here is below five (rainwater). The oyster shell brings it up gently and naturally to 7.4. Ph greater than eight requires a completely different approach. I can't help you there.
Put a screen over the end of the feed tube coming from the pump to prevent medium from getting sucked into the tube and blocking the flow when the pump shuts off.
Supplement your feeding with liquid kelp. The fish alone cannot provide all the nutrient needed. Without the added nutrition I got white fly infestation. I got my best growth and fruit when I started adding kelp.
My inside guppy tank does not provide enough nutrient to produce fruit. My outside tank with a mess of goldies and the addition of kelp does just fine.
I know there's a ton of other stuff I should be telling you but it hasn't floated to the surface.