I don't know if I can afford a 120. That's bigger filtration more lighting and more money
As others have said, the cost for the equipment is pretty much identical. On this site (I can't vouch for this company - I've never bought anything from them), the price differential for a 120g vs 90g with pre-installed overflow is $270. I can guarantee that you will have forgotten about that $270 in a year's time.
I started my first reef in a 90 gallon all-glass in 1993. I still have the tank, but it is setting empty in the basement at present. The reason is that it's just too dang narrow from front-to-back.
But, if you're suffering sticker shock (and it's a really common disease with your first reef aquarium!), here's a way to ease into this (addiction) without dropping a
ton of cash:
First, re-think your fish ambitions. Some rabbitfish get really large, and there are literally hundreds of cool species that will be perfect for a 75 gallon or less. Insisting on a reef with a school of yellow tangs or several large angelfish means big money.
Go to your local Petco. Until the 27th, they will sell you any size tank they have for $1/gallon. My local one had a 75 gallon, several 40 gallon breeders (very popular for a small tank), and a 60 gallon. If you go for the 40 breeder,
buy two. Also buy a 10 gallon, or better, a 20 gallon high. These are your quarantine or "emergency" tanks. It's a good way to mix up saltwater that doesn't take up all the space of a brute trash can.
Buy a hole drilling kit and an overflow from gla$$hole$.com. Drill the tank yourself and install one of their overflows (they are far superior to the space-hogs that All-Glass and Perfecto put in their "Reef Ready" tanks anyway). Even if you have to buy a high-end lithium ion drill to do it, you're still going to come out ahead, and you have a nice drill to boot.
The reason you are buying two 40's (or 2 60's, or 2 75's) is that if you break one drilling the overflow, you've got a spare. If you don't break one, you have an instant live-rock curing tank that you can then sell for what you paid for it when you're done.
Build a stand. For a smallish 90, 75 , 60 or 40 breeder, you can make a perfectly serviceable stand that will look good even if you don't have much in the way of carpentry skills. Follow the advice on this forum - there are lots of threads with cool stands made of screwed-together pine boards from the home center.
OK, you have your tank with an overflow and a stand. Here's the absolute minimum equipment list for a manually-maintained (and much cheaper than an automated) tank from a guy that used to do it before the advent of dosing pumps, aquarium computers, and lots of other fancy gear that was utterly unaffordable back in the day:
Skimmer. - I'd recommend spending the dough for one of the less expensive reef octopus ones. Cheaping out here will get you a very noisy, ineffective skimmer that needs constant fiddling to work right (I have several in storage that could be described this way). If you want to save cash, then get a good, column-type air-stone driven skimmer and Coralife luft pump. Wooden airstone skimmers went out of style because they need more maintainence, not because they don't work - some think they work better than even needle-wheel skimmers.
Sump - Remember that 10 gallon tank? It'll work fine for a sump if you have a 40 gallon breeder, otherwise you can use a rubbermaid storage container (I'm not joking - they work quite well, and they cost $7).
Pump - Again, don't go
really cheap here. Get an eheim, they're bulletproof. Otherwise, a troll through the equipment forum on reef central - you'll quickly get an idea about what brands to avoid. You
don't need a pump big enough to turn your tank over 20 times an hour. Presuming you got a good skimmer, you can go with 5-8 times an hour, many successful reef tanks have return flow this low.
Powerheads for circulation - get hydor koralias, or if you need to go cheaper, get zoo med powersweeps. The zoomeds work well, you'll just have to do more maintenance on them to keep them oscillating.
Heater - no question, get an eheim-jager. They're only a little more money than the dirt-cheap no-names, and they're also bullet proof.
Lights - If you can afford it, get LED lights from buildmyled.com. They don't come with fancy weather effects, but they're robust, easily repairable, and no LED fixture is going to hold its value, even the top-of-the-line german-made GHL fixtures. The LED system will make things cheaper for you, because you won't have to have a chiller, and you won't have to keep your house/apartment AC cranked way down in the summer to keep your reef tank from dying. Failing this, go with a T5 fluorescent fixture. They'll be hotter and consume more electricity, but they are proven technology.
Test equipment - this is a requirement, you can't keep a reef without it (at least for long). You need, at minimum, a hygrometer (you don't have to have a refractometer), a reliable thermometer, and an ammonia test kit (tetra's $5 kit works fine, you will only need it for the start-up), a calcium test kit, and an alkalinity test kit. You can wait until later to pick up phosphate, nitrate, magnesium etc... kits.
An RO/DI system. This is not optional. THe only way you can get around this is if you purchase your purified water from a local fish shop, and that's going to get really tiresome really quickly (not to mention expensive).
Miscellaneous: 1/2 gallon plastic jugs that vinegar comes in, a few airline needle valves, some E8000 glue (not silicone, though you can use epoxy in a pinch), and some airline tubing. You'll use these supplies to make a drip jug for kalkwasser and reef buffer. Plastic 5 gallon buckets - Lowe's sells some nice food-grade ones that won't leach things back into the water for $3 each.
Extra submersible heater - you need this to warm your saltwater for a water change. Alternatively, you can use your microwave and some quart mason jars (heat the water in the jar, cap it, and set it into your saltwater to warm it to room temp).
That's about it for a basic, totally-manual reef that will grow coral and keep fish, other than the live rock, sand (if you use it) and critters/food. I grew enough coral in the mid-90's to have to give away a lot of it with just this basic set-up.
Enjoy, and welcome to the slippery slope.
