Hiya and welcome
You would get more replys if you posted in the planted section, so if you have anymore questions regards setting up a planted tank post them in there, people are helpful in there including me
Naw only joking, but do post your threads or questions in there, also read through the threads and pinned topics in that section they will help you a lot.
Ill try and answer as best i can.
Not sure about your halides, they probably arnt the right spectrum anyway (but maybe they are) you want to aim for somewhere between 5500 kelvin and 10000 kelvin, the ideal is about 6500k but many use higher K ratings than this with good success, but there are so many tubes on the market and lots of choice its really comes down to personnel preference.
The T5s are definatly a good choice, this is what i use, i use Interpet Daylight 6500k tubes, T5s pack a lot of punch over conventional T8 tubes and are definatly the way to go because of their size and the fact you need less tubes than if you were useing conventional T8 tubes.
Anyway you can read up on lighting but it is probably the most important aspect of growing plants successfully along with the substrate that you use (the gravel, more on this later) but your halides might do with different tubes in them of the right spectrum.
You seem to understand the watt per gallon WPG guideline, basically if you want to grow low light plants you would need between 1 to 2 WPG, between 2 and say 2.5 WPG you could grow low and medium light plants, and anything over 3 WPG you can grow most anything.
Now with your 5 WPG this would be considered very high lighting, anything over 4 would be considered very high lighting, because dont forget you will be useing reflectors and this would increase your lighting even further, i know in marine setups high light is important but you probably dont need that much as a beginner in planted tanks, im not saying it cant be done, but with that much light going things would grow very fast and your tank would need a lot of attention to stop things getting out of hand to quickly.
Basically you can have a successfully planted tank and be able to grow everything with 3WPG and the use of the correct reflectors.
If you go over say 2.5 watts per gallon you must supply co2 into your tank (co2 carbon dioxide) at this level of light it is a nescessity for the plants, you can do DIY methods with plain plastic lemonade bottles filled with sugar and yeast and water and this will generate co2, but for a tank your size you would need a pressurised co2 unit and this will regulate the flow of co2 into your tank, their are many kits available check it out, but this would be a must if you go 3 or more WPG.
Not sure about your wet dry filter, i use an eheim 2215 external filter, basically when you have the tank planted and up and running it works as a filter, one of the benifits of planted tanks is that the plants use up most of the ammonia and nitrates that your fish will produce, the most important thing about the filter that you use is that you are trying to achieve minimal surface agitation in order to keep the co2 in the water, to much surface agitation and you will lose the co2, so most people use some sort of external filter.
So basically you dont need the powerheads.
Yes uv sterilisers are useful and lots of people use them, do some research on this.
The other important aspect that you need to consider is the substrate, ordinary gravel wont do in a highly lit planted tank, as ordinary gravel is inert and contains no benificial minerals for the plants, so you need to look at something else.
The most popular substrates would be Seachem flourite, Eco complete, or you could use Laterite, the first 2 would be the best IMO but are hard to come by in the UK (and impossible in Ireland) but you could look around, or you will get them online at.....Aquatics online.....sorry no link....do a google and look under the section.....freshwater planted substrate.
These are all expensive but you can mix the flourite and laterite with ordinary gravel to keep the cost down.
I just seen you mentioned a fluval 404 that would be fine depending on your tank size.
Anyway and then of course you have fertiliser, but thats a different storey and would take to long for me to explain.
Basically its a bit of a steep learning curve in the beginning, im still feeling my way around myself, but its all online, everything you need to know you can check out online, so just read as much as you can and do loads of research, also try and buy good equipment in the beginning even if you have to save for a bit, but you already have the makings of a planted tank so go for it.
Best of luck.
