New Here

makeouthill · Monday at 5:28 PM

Hello everyone, I am purchasing a used up and running 20g Long off of marketplace on Saturday. For one heck of a deal, I’ve been keeping fish my entire life along with other animals and been too afraid to tackle saltwater like many of you at some point in time. I have the description of the listing everything that is coming with the aquarium down below. Please feel free to share any advice and steps I should take keep it running properly. I plan on trading the cardinals in and having a pair of clowns, some inverts, beginner corals, and a firefish (possibly a goby as well) I would love recommendations on what corals and or fish to get as well

ps- I don’t know all of the lingo used within the saltwater community so try to not use a lot of abbreviations lol

pps - I know a 40gal is recommended for starting out i’m aware of that but the guy is selling it to me for $100 so I’m willing to risk it

Thanks!!

BryanM · Monday at 6:03 PM

I would make sure you have test kits, RODI setup, and just read up here about the general ideas on getting started and what to do.

RODI to me is the life blood of our systems.

Psyduck · Monday at 6:04 PM

56longroof · Monday at 6:07 PM

Welcome aboard. Definitely buy a RODI and don't be afraid to ask all the questions you need. There are alot of knowledgeable and helpful folks here.

makeouthill · Monday at 8:29 PM

56longroof said:
Welcome aboard. Definitely buy a RODI and don't be afraid to ask all the questions you need. There are alot of knowledgeable and helpful folks here.

thanks!

Fish Fan · Monday at 11:15 PM

Welcome to saltwater tanks!

All good advice so far.

As mentioned, look at an RODI (Reverse Osmosis with DeIonization) water filter system, the "RO Buddy with DI" is a popular ultra-budget choice, and certainly they get more expensive from there. But it's really important to have nearly pure freshwater to make new saltwater, or for "topping up" fresh water that evaporates (only freshwater evaporates, salt is left behind, so don't top off with saltwater, use fresh!).

A 20 gallon tank is a fine starting point, 40 gallons is a suggestion, not a magic number. At 20 gallons, if you don't have an RODI filter just yet, you can sometimes buy both premade saltwater and prefiltered RODI freshwater from your local fish store. You can also get gallons of distilled water from any grocery store, pharmacy or Mega-Lo-Mart in your area. Should be a little over a buck/gallon. Just know that hauling all that water does get old in a hurry. An RODI almost because a necessity if you stay in the hobby a while, but you can start by buying water if you have to.

You're absolutely going to need a way to measure the salinity of the tank. There's an inexpensive "swing arm" hydrometer that's been around longer than I have, some like it, but I think it's problematic (think bubbles on the swing arm). A good glass hydrometer really can't be beat for accuracy, but they are cumbersome and inconvenient to use. Get yourself a decent refractometer and some 35ppt calibration fluid (most will include this). They can be had for between like $30-$50. Double check that the hydrometer is for keeping salt water tanks, and not, for example, home brewing. They are not quite the same, but it should be clearly noted.

EDIT: Here's an Amazon refractometer, great reviews, 15 bucks

You'll need some basic test kits to get going. I'd have at ammonia and nitrate on-hand for the move and right after, pH is good to have too, and then when you get into corals you can explore more tests as needed. For both budget and easy to use/read, look at the Salifert brand kits. If you have the money, many like the Hanna Checkers, which are digital. Try to avoid using the API brand kits, they are generally considered not very accurate by most members here. You can also usually bring a sample of water to your Local Fish Store (LFS) for testing.

That Kessil light is the best score in your package, in my opinion, I love my Kessil lights. But I'd keep my eyes open for one more down the road. Because of the length, that tank really needs two Kessil A80's. Not just for corals, because even in your pic you can see that you have a lot of shadowing on each side of the light. It's fine to get you going, you could even place your first few hardy corals in the middle so they get some light, but I think you'll have a hard time growing anything on the far ends of your tank. Keep a lookout for a good deal on another A80, I see them used all the time.

If there was "a couple" Aptasia (a small "pest" anemone that can grow out of hand quickly in our tanks), you may seen more, just to be aware of that.

Nothing wrong with the Red Sea "Blue Bucket" salt mix, but it has elevated alkalinity, calcium, magnesium, etc. that's really only important for corals. If you have just fish and "typical" inverts like hermit crabs, a basic sea salt mix is fine, no reason to spend extra on salts for coral growth at this point.

That stand looks nice lol! Do you have a plan for a stand? A 20L can be supported by a sturdy dresser or the like, or certainly you can buy an aquarium stand, or DIY a stand.

Do you have a plan for the move? How far do you have to go?

This article is a great way to get going in this hobby:

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 no where near simple. This task is going to take patience, a ton of...

www.reef2reef.com

And I like this video series, just don't buy anything until you ask here at Reef2Reef first ;-)

There's A LOT to this hobby, so I likely left something out ;-) Keep reading, researching, and go slowly.

I hope that helps, let us know if you have any questions about anything. Good luck!

makeouthill · 2025-01-15T01:49:02-0500

Fish Fan said:
Welcome to saltwater tanks!

All good advice so far.

As mentioned, look at an RODI (Reverse Osmosis with DeIonization) water filter system, the "RO Buddy with DI" is a popular ultra-budget choice, and certainly they get more expensive from there. But it's really important to have nearly pure freshwater to make new saltwater, or for "topping up" fresh water that evaporates (only freshwater evaporates, salt is left behind, so don't top off with saltwater, use fresh!).

A 20 gallon tank is a fine starting point, 40 gallons is a suggestion, not a magic number. At 20 gallons, if you don't have an RODI filter just yet, you can sometimes buy both premade saltwater and prefiltered RODI freshwater from your local fish store. You can also get gallons of distilled water from any grocery store, pharmacy or Mega-Lo-Mart in your area. Should be a little over a buck/gallon. Just know that hauling all that water does get old in a hurry. An RODI almost because a necessity if you stay in the hobby a while, but you can start by buying water if you have to.

You're absolutely going to need a way to measure the salinity of the tank. There's an inexpensive "swing arm" hydrometer that's been around longer than I have, some like it, but I think it's problematic (think bubbles on the swing arm). A good glass hydrometer really can't be beat for accuracy, but they are cumbersome and inconvenient to use. Get yourself a decent refractometer and some 35ppt calibration fluid (most will include this). They can be had for between like $30-$50. Double check that the hydrometer is for keeping salt water tanks, and not, for example, home brewing. They are not quite the same, but it should be clearly noted.

EDIT: Here's an Amazon refractometer, great reviews, 15 bucks

You'll need some basic test kits to get going. I'd have at ammonia and nitrate on-hand for the move and right after, pH is good to have too, and then when you get into corals you can explore more tests as needed. For both budget and easy to use/read, look at the Salifert brand kits. If you have the money, many like the Hanna Checkers, which are digital. Try to avoid using the API brand kits, they are generally considered not very accurate by most members here. You can also usually bring a sample of water to your Local Fish Store (LFS) for testing.

That Kessil light is the best score in your package, in my opinion, I love my Kessil lights. But I'd keep my eyes open for one more down the road. Because of the length, that tank really needs two Kessil A80's. Not just for corals, because even in your pic you can see that you have a lot of shadowing on each side of the light. It's fine to get you going, you could even place your first few hardy corals in the middle so they get some light, but I think you'll have a hard time growing anything on the far ends of your tank. Keep a lookout for a good deal on another A80, I see them used all the time.

If there was "a couple" Aptasia (a small "pest" anemone that can grow out of hand quickly in our tanks), you may seen more, just to be aware of that.

Nothing wrong with the Red Sea "Blue Bucket" salt mix, but it has elevated alkalinity, calcium, magnesium, etc. that's really only important for corals. If you have just fish and "typical" inverts like hermit crabs, a basic sea salt mix is fine, no reason to spend extra on salts for coral growth at this point.

That stand looks nice lol! Do you have a plan for a stand? A 20L can be supported by a sturdy dresser or the like, or certainly you can buy an aquarium stand, or DIY a stand.

Do you have a plan for the move? How far do you have to go?

This article is a great way to get going in this hobby:

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 no where near simple. This task is going to take patience, a ton of...

www.reef2reef.com

And I like this video series, just don't buy anything until you ask here at Reef2Reef first ;-)

There's A LOT to this hobby, so I likely left something out ;-) Keep reading, researching, and go slowly.

I hope that helps, let us know if you have any questions about anything. Good luck

holy crap man this was an amazing reply to my post tbh and it so much for the detail and information provided I will most definitely be looking into the RODI system as well as an extra light and salts down the road, I plan on using my dresser for the stand and the drive is 45 min one way, so I plan on getting home depot buckets with lids for the water and fish (i’m going to go the the closest lfs to trade them in so they won’t be stressed on the ride home) and and rocks will be in a separate bucket as well so they won’t break the tank glass. After that it’s a another 45 min home and i’ll set everything up ASAP