I'm going to start up my new reef aquarium in the coming weeks/months.

I've had a freshwater 1000 litre tank for 6 years now and want to branch into marine now. My first tank will be about 250 litres.

I'll be asking a series of questions and realise many of these will have various opinions and I'm looking forward to weighing through them all.

To start with

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  1. I'm in Auckland. Are there any public Marine speciality shops around?
  2. Are there any good online retailers in NZ (fish as well as parts)?
  3. Are there any and who are trusted TradeMe retailers?
  

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  4. What's everyone's recommendation for sump size on a 200 litre main tank?
  

I'm in Auckland. Are there any public Marine speciality shops around?

There is Hollywood fish farm.

There is Hollywood fish farm.

Yes and I believe Royal Oak is the best. Any others?

Also Aquaworld nth shore, online as well wonderworld rotorua.

Sump as big as will fit in the cabinet allowing room for any other gear you may want to put in there.

I got skimmer coral rock and coral sand all for $300 if you need it

PM me if you need equipment etc,

got loads of second had stuff lying around

I got skimmer coral rock and coral sand all for $300 if you need it

How much coral?

Also Aquaworld nth shore, online as well wonderworld rotorua.

Sump as big as will fit in the cabinet allowing room for any other gear you may want to put in there.

So they sump can be any size?

Is there a minimum size you would want to use?

The minimum size will be dictated by what you want to put in it.

Sumps can contain:

Filter socks

Media (carbon, GFO, etc)

Heaters

Skimmers

Refugium

RO top-up containers

Auto Top Offs

Algae turf scrubbers

The biggest item will be your skimmer. Some decent skimmers can be very large, so you need to research what you consider to be a good skimmer in your price range.

You need to decide if you want a refugium, what you will be putting in it, and subsequently how large it needs to be. Will you have multiple media chambers? etc

The idea is to go larger than you think you need so that you have room in the future to upgrade, and also so that you have a bigger buffer zone for any fluctuations in toxins/minerals.

I think if you went any smaller than an 80L sump you would struggle to fit everything in.

You could go 60L if you plan on only doing basic media, skimmer, ATO and heaters, but it will limit what size skimmer you can put in it.

As long as the sump will hold the amount of water that will flow into it when the pumps go off it will be sweet, but as Kinnadian said, you want a good sized one so you can have all the equipment you want comfortably fit in it.

Yeah good point, to clarify the water level in the sump needs to be X volume below the maximum volume of the sump, where X is the maximum volume that can drain through the display tank overflow if the return pump fails.