Plasticgoat

Parzi doesn't work well with certain strains of flukes

High level of copper to a certain level effective against flukes too. Use seachem cuppramine.

1 + 1 no benefits. The air intake about the same means the skimmers will be competing against each other. Might as well get 1 skimmer with very high air intake.

Uv will affect copper. The uv will unbind the copper in its safe form and the copper will become poisonous

Dont use ohf for tank. Try not to use a filtration system that allows dirty to accumulate. Get a powerful skimmer. U can use the fine sock at the bottom of your overflow pipe but do wash it often.

6 x 2.5 x 2.5 Sump 4 × 2.5 x ? Use the aquaroache towers to get the rockscape high. Have to run reactors. Changed to skimz pyramid skimmer recently. Chiller daikin 1hp. Ati T5s light.

I got sick of hilea chillers water tank rusting n leaking. I also find that you can't really service chillers much. I currently use daikin 1hp chiller. Super reliable any air con service person can service it. The downside is the hot air it emits is rather warm. I would suggest you mount the compressor far away. Outside your unit if possible.

Between T5 will be ok for corals.

Go without the hob filter. Try to avoid filtration that would contain stuff within the water. Ok without sump but get a good hang on skimmer. Ur tank is small u can buy rodi water from farms, use mineral water. People overseas use tap water with seachem prime with salt. I am not sure if you wanna use tap water as your tank is small and moreover I am not sure about the corals you intend to keep. I have a fairly large tank.you can check out my video.

My tank