Considerations for your first saltwater tank

Considerations for a learning tank

Start small

We suggest starting small. That seems to go against the prevailing wisdom these days. You may have heard larger tanks are more stable and less maintenance. That is true to an extent. However, your investment will scale with the size of a tank. For example you will need larger filtration, more lighting, and lots more equipment. Bigger tanks open up the possibility to more fish and livestock, but as a beginner… you can manage the “cost of learning” through limiting your initial investment to equipment and livestock. Besides, there are lots of great ways to start small and still have a rewarding experience. You will learn about the things that are important to you and impactful to your tank first hand, without playing guess and check with a huge tank and expensive equipment.

Small doesn’t necessarily mean as small as you can go… we wouldn’t recommend starting below 10 gallons for example. A good beginner range is 10-55 gallons. The trade offs are still there, larger will be more stable with more expensive equipment, while the very small side will be more hands on, but there are lots of savings to be had.

Under stock with hearty livestock

Some fish are more stress resilient than others. Some have a wider range of tolerances. The same is true of corals and invertebrates. Low stress and tolerance isn’t the only consideration. Size is important too. Bigger fish need bigger tanks and produce more waste. You can make your tank maintenance easier while you learn the ropes and develop good habbits by picking fish that are smaller so a missed water change isn’t the end of the world. Another stocking consideration is aggressiveness and compatibility.

In stocking choices, a little research goes a long way.

We encourage you to do additional resources but here are some ‘starter’ marine fish to consider in your first tank.

-Ocelaris Clown fish: a true classic of the hobby and for good reason. Aside from the clown fish association with the Pixar film Finding Nemo, these fish are very popular in the hobby for good reason. First, they are very stress tolerant and hearty. Next, they can be kept in a smaller tank. As I mentioned at the top, these were my marine fish I kept in a 15 gallon tank, with no issue. With a little more experience, I would actually advise a little more space for a pair of Ocelaris, however, from a bioload perspective, with good maintenance, that is manageable.

-Blue damsel. This might be controversial. People say damsels are too aggressive to be beginner fish and don’t pair as well as clowns… this is true, but my caveat is as the sole fish in a small tank they are excellent starter marine fish. In larger tanks that aggression is dispersed and there is more hides and less interactions. Bullies for their size sometimes, their weight class is small so they won’t stress larger fish too much. Other than some aggression they tick a lot of starter boxes: hearty, low bioload and do fine in small tanks.

-fire fish: bring a splash of bright red to your tank with the firefish goby. Moderately hearty with a small size, they can be added to tanks 20+ gallons. They are a little timid. So if you want to add to a tank with something more aggressive like damsels or clowns, we recommend to add the fire fish first before the others and/or have a large enough tank where bullying is lessened (eg 50+ gallons).

just a few to consider, but there are many great starter fish to consider.

Add lots of coral rock and let it cycle!

Coral rock whether manufactured, live rock or dry rock will become the basis for your nitrifying bacteria and the habitat for you tank. Adding more never hurts—although think about your scape—and just adds more surface area for bacteria growth. This will keep ammonia at bay and add stability.

It is recommended to wait a few weeks before adding livestock to let the nitrogen cycle establish in a tank. This means biofilms growing on rock that will reduce ammonia to less toxic nitrate. It’s always recommended this is verified through water testing. Also, you need a nitrogen source in a new tank. Fish food, a shrimp (classic method), or measured out ammonium will do the trick. Bottled bacteria will also help speed things up to establish the nitrogen cycle (Dr. Tims’s has a lot of good reviews and science to back it up).

If you get live rock or used dry rock it’s a good idea to test phosphates as old live rock can accumulate phosphates that can leach back out into the water. It’s less toxic to fish at low concentrations <2ppm, but can lead to lots of algae growth and could be an issue for coral that do best in very low concentrations eg <0.1ppm for SPS. Live rock can be rinsed in a low concentration 1:10 or 1:20 muriatic acid to dissolve old waste and the excess phosphates. Do this outside and follow all safety precautions.

Don’t forget the clean up crew

Not as exciting as fish, clean up crew serve important functions in our tanks. Not to mention a new tank will go through ugly stages of algae growth. Getting some snails and hermit crabs in their early keeps the worst at bay.

Some recommendations and recruits:

1: add lots of clean up crew. The often shared recommendation is 1 snail per 2 gallons and 1 hermit crab per 5-10 gallons. That’s a lot and maybe cost prohibitive, but it’s a good reminder your tank can handle a lot of clean up crew!

2: adding in waves spreads out the risk of loss. Especially in a new tank where there might not be a ton of algae yes

3: not all algae eating is very efficient. Dinoflagellates and bryopsis have low palatability to most algae eaters.

4: algae eating isn’t everything for a clean up crew. Algae eaters break down larger like organic waste and get it to the water column for easier export via the skimmer or filter socks. Most clean up crew members are small snails and hermit crabs. Sand mixers like Nassarius snail serve other functions while also being part of the team. Mixing sand is considered aerobic, and last little anaerobic area for denitrification.

Algae eating snails:

-Trochus

-Astrea

-Turbo

-Cerith

sand mixing snails and detritivores:

-Nassarius snails

-bumble bee snails

-red and blue tipped hermit crabs