Welcome to Reef2Reef and to saltwater aquaria!
I have a few thoughts that I hope will help
First, did you maybe mean that you have or are purchasing a Seapora tank, and is it this one?
This Seapora Standard Aquarium is a 30 gallon extra high model that has been made with the highest quality materials available. It includes a top and bottom injection molded frame for maximum support, diamond polished edges, and black silicone. Size 24" x 12" x 24" Seapora Dimensions L x W x H...
bluefishaquarium.com
Did you already purchase this tank?
If so, I'm going make a few suggestions largely through the lens of a budget reefer, like myself
If you have a larger budget for gear, please let us know and I'm sure we can help you spend your money
Heater:
You generally need between 3 and 5 watts per gallon of water, with smaller tanks needing closer to the higher range. For your 30 gallon, I'd look for a 150 watt heater. Personally, I like titanium heaters like the ones from
Bulk Reef Supply (<needs a heater controller) or those by Finnex or Hygger. My humble suggestion for a budget glass heater is this one from Marina. I've had several of these heaters and they've worked well for me, mostly for my freshwater tanks:
Marina heater on the big online bookstore
Please consider using a heater controller that will prevent your heater from malfunctioning and catastrophically overheating your tank. One popular choice would be the heater controllers from InkBird, like this one:
InkBird Heater Controller on the big online bookstore
Filter:
You have some options including drilling this tank for an overflow and using a sump (which would be a great choice!) if the tank's glass is not tempered (
here's an easy test to check for tempered glass). Some use Hang-On-Back (HOB) overflows with some success, but these can potentially malfunction and cause a flood. For your tank and in keeping with my suggestions for a budget build, I would suggest that you just use a HOB filter for this tank. There's lots of options to choose from, but I think the most well liked HOB filters are the SeaChem Tidal and the Fluval Aquaclear. Between the two, I much prefer the AquaClear because it is tried and true, and customizable to be even more efficient for a saltwater tank. You can search and find many tips, tricks, and mods for the AquaClear filters. I would get the largest you can afford, don't go by the suggestion on the box. Get an AquaClear 70 or even 110.
Fluval AquaClear 70 on the big online bookstore
Skimmer:
You don't need one
For a 30 gallon tank, you can manage nutrient export just by doing regular, partial water changes, especially if you'd like to keep some of the easier going soft corals and Zoe's. Unless you decide to go for the sump option I mentioned above, the only real option for a skimmer is a HOB, and I don't think you could fit both an HOB filter and an HOB skimmer on the back of your tank at the same time. You could run one or the other, but I'd go with the AquaClear HOB and water changes.
Wave Pump:
Very important! Circulation in a saltwater tank is very important, especially if you want to keep corals, and necessarily needs to be much higher than a typical freshwater tank, which is why I recommend the largest AquaClear filter you can afford above, it will only help with circulation.
Popular brands of budget circ pumps include Jeboa/Jacod (<basically the same Chinese company), Hygger, Fluval, Hydor, and Sicce. I'd suggest this Jebao for your tank:
Jebao SOW wave maker from the big online bookstore
Lighting:
This is going to depend on what you want to keep. Do you want to keep corals? Then you will need a light capable of supporting their growth. On the budget side, I'd suggest looking at Noopsyche, Hygger or NiCrew.
Livestock:
If you have or are getting the tank I linked above, choices for fish will be limited. The 24" x 12" foot print is basically the same footprint as a 15 gallon tank, and swimming room is important, which is going to limit your choices of fish. Tangs are not an option. A pair of Clownfish may do well as would smaller Gobies and my favorite little fish, a Tail Spot Blenny.
I don't mean to sound negative especially if you already purchased your tank, and I know you mentioned some space limitations, but if you have an opportunity to choose another tank I'd suggest that you consider that option
There's nothing wrong with the tank you've selected, though in the saltwater world most place value on front-to-back spacing, and not as much on vertical. This gives more of a footprint to create an aquascape, and to allow fish to swim.
Here's a list of fish stocking ideas from another forum, and while kind of dated, it may give you some ideas. Again, I would consider you tank a 15 gallon in terms of fish stocking, just because of the dimensions:
Fish Stocking Guide For Nano Reefs By lgreen (copyright 2005-2013) Note: You are welcome to place a link to this guide on another website or forum, however, do not place the actual article itself on your forum or website with out my permission. Your link must direct traffic to it's original form ...
www.nano-reef.com
Here's a great article on saltwater tanks if you're brand new:
The Supreme Guide To Setting Up A Saltwater Reef Aquarium Introduction The marine environment is one of the most complex systems on the planet. The aquarium you are about to set up is only a tiny sliver of the vast ocean, but it is nowhere near simple. This task is going to take patience, a...
www.reef2reef.com
Here's beginner video series that I personally think is a good watch:
New to saltwater aquariums? Learn how to set up and maintain a thriving reef tank with our complete Saltwater Aquarium Beginner’s Guide from BRStv.
www.bulkreefsupply.com
I hope this helps, and good luck!
