Advice On A New 15 Gal Saltwater Build

I think the 15g sounds pretty nice with you're planned stock. You're opening up a can of worms asking for general advice, haha, but here's some things that popped into my head while reading.

Water temp should be about 78°F. pH will be around 8. How are you planning to provide saltwater? Tap water is generally unsafe for salty tanks, particularly if you want corals. If the tap has a TDS below... hmmm, maybe 100, (50 would be better), then the tap may be safe for a fish only tank. This is assuming that it doesn't contain dangerous contaminants, like heavy metals. Really though, I never recommend tap water, and it would be better if you go with RO/DI. You can by RO/DI or distilled from a grocer, or the fish store, then mix it with marine salt at home. Alternatively, you could buy premixed from and LFS if you have one close by that sells it. I'd say for a 15g, you'll need to make 3g's a week for regular water changes, but don't forget about fw top offs. The tank's water will evaporate, but salt won't, so salinity levels need to be managed every single day. You'll either need to manually top off, or get an automatic top off unit, (ATO). There's no telling how much fresh water you'll need per week, as different factors come into play with different tanks. A guess? Probably need around 2 gallons of RODI per week for top offs.

Filtration - rocks in your tank will handle biological filtration. BB will colonize the rocks and maintain your cycle. An HOB isn't a bad idea for some mechanical filtration, though sponges and floss need to be cleaned or replaced often or they'll produce nitrates.... not a good thing. If you want corals or sensitive species, (like inverts) you'll want to keep nitrates super low. Like under 10ppm. This brings up another great option for HOB's. If you get a basic box style, like an Aquaclear, then it can be easily modified to be a small refugium. A refugium is for growing macro algae like chaeto. As the macro algae grows, it's using nutrients, so this is a form of nutrient reduction. Simply said, it'll help keep nitrates and phosphates low.

If you're unsure about corals, go ahead and start with a fish only tank. This is my biggest piece of advice... you don't need a fancy light for a fish only tank. It is only for your viewing pleasure, so you can even use an old fw light or whatever else you already have or can buy cheap. If you're sure you want corals, start saving for the best reef light that your budget allows. It stinks buying a cheap reef light, (because they're not all that cheap), and then wanting an upgrade less than a year later. This means the light will be paid for twice. I did that. Wish I wouldn't have got that first one and saved that money towards a better light from the start. The first light purchase has almost turned into a waste... unless I can mount it over another tank.

Have you seen @Nart 's excellent guide on starting your first reef tank? It really is great one, and I wouldn't have been half as successful without this guy's help.
Nart's Budget Nano Saltwater Guide For Beginners

 

Awesome! I love to help when I can. Trust me, there's no rush either. We can talk all you want, and I very much appreciate you taking your time to research and plan.

 

First thing that comes to mind when you say water changes and maintaining water is a refractometer. That's what we use to measure salinity, or the salt content in water. Years ago, refractometers were unaffordable for the average Jo, and thus, hydrometers were used instead. Hydrometers are still sold and sometimes recommended at chain fish stores. Don't fall for it! They are notoriously inaccurate, and you can pick up a refractometer for about $20 on Amazon.

Second thing with maintaining water and cycling - filtration. I'm assuming you're familiar with the nitrogen cycle from doing freshwater, and cycling in saltwater is just the same. You add an ammonia source, test the waters regularly, and keep dosing and testing (possibly do a water change or two if levels get too high) until the cycle is complete. Filtration is different though. In a saltwater tank, beneficial bacteria will colonize the rock in the tank rather than media in a filter. You may not even need media in a filter if you have enough rock. More on that later, if you want.

Test kits - API is fine for ammonia and nitrites, but is not great for nitrates, particularly when you're done with the cycle and are keeping nitrates low. You'll want a kit that can read accurately below 10ppm. Look into Salifert, RedSea or Nyos for test kits.

I don't have a lot of time to make this a long one. I will be glad to converse with you about quarantining and disease another time time though. If you'll have corals one day, there will be very, very few medications that you can use in the tank without hurting and quite possibly killing the corals. When you've spent a lot on corals, and taken pleasure in their care and growth, you will not want to risk getting the display tank sick. (Corals are living things too, truly amazing animals in fact... and when they die, it's our fault. )

 

Eek! So sorry I've been missing your posts. I'll be home soon and will be able to give a thoughtful response.

 

Hey Watermelon Have I directed you towards this great thread yet?
Nart's Budget Nano Saltwater Guide For Beginners

I'm sorry, I just don't even know where to begin with general questions like, "What do I need to know?" Lol... it's a journey for sure, and a year ago I didn't know half of what I do now about reefing. The guide above will answer lots and lots of questions. Start slow and concentrate on substrate, rocks and water for now. I spent a few months gathering supplies, saving for a good light, and researching as much as I could before water ever hit my tank.

Water is a big one. You have to decide how you're going to provide saltwater for this tank. You can possibly buy saltwater from your LFS, and this is not a bad option in smaller tanks. Alternatively, you can buy pure water, (RODI or distilled), and mix it with marine salt yourself. The salt will contain everything you need to achieve the correct pH, GH, KH, (which is more often referred to as alkalinity on the salty side), and all the other trace minerals that are found in the ocean. Also, don't forget that a saltwater tank needs freshwater added to it daily, and this water must also be pure. Salinity swings are dangerous for livestock and of all the parameters there are to manage in a saltwater tank, maintaining a stable salinity is the very first step. In nano tanks, salinity swings can happen fast, so smaller tanks are best managed with an automatic top off unit, or ATO.

I appreciate your kind words, but there is still so much I don't know, and I still have those I rely on to answer my questions as well. Please do read Nart's guide that's linked above. This is by the guy that helped me so much when I got started, and it will be much easier for me to help you if you can come back with more precise questions. I will be more than happy to help you get this nano tank started, as nano tanks are where I have experience. My little reef is only 20 gallons.

Oh yeah... you can certainly have some blue hermits, just be sure the species you select is reef safe. You might not get coral right away, but it can be rather difficult to catch inverts once they are in the tank. Crabs that are not reef safe will eat coral, oh no! Safe hermit crabs will eat algae so they can be a good part of the clean up crew, (CUC), which you will absolutely need in a marine tank. They can be added to the tank as soon as the cycle is done.

 

Oh my goodness... The alert system here isn't perfect, though I've found other ways to manage myself around here. Sometimes something slips by me though. I'm terribly sorry that I've left you hanging for so long. I don't have time right now to address everything but promise that I'll be back after dinner and getting little ones off to bed.

 

Thanks for the kind words.

So, you may find that many disagree, but I do not see any problem with starting the hobby on the saltwater side. You may be quite new, but some basic info is the same, and the hard stuff will start making sense with experience. Believe me, I felt totally overwhelmed a little over a year ago when I first started wrapping my head around running a reef tank, but as you start putting your research into practice, the knowledge will stick.

You are familiar with the nitrogen cycle, yes? Just the basics will do. Ammonia is produced by fish, the breakdown of their waste, as well as leftover foods or pretty much any kind of dead organics. You need beneficial bacteria (BB) to colonize in your system so they will convert ammonia to nitrites and then nitrates. Here's where thing's start to get a little different between fresh and salt... In freshwater tanks we rely on filter media like sponges or bio-balls. Bio-balls is a general term, as is ceramic media for small pieces of some porous material. Here are a few examples.
https://www.amazon.com/Fluval-Bioma...8&qid=1524881539&sr=1-4&keywords=fluval+media

https://www.amazon.com/Substrat-Bio...F8&qid=1524881403&sr=1-4&keywords=eheim+media

https://www.amazon.com/Seachem-Matr...1586&sr=1-1&keywords=seachem+matrix+bio+media

Any of these will host the type of BB (two different strains of aerobic bacteria) needed to break down ammonia and nitrites, which are both toxic at any level, and therefore dangerous to your livestock. Nitrates can build a little but we do water changes to ensure that nitrates don't build to toxic levels. Lots of freshwater tanks are quite safe with nitrates no higher than 30ppm, but there are more sensitive fish like Discus, who need nitrates to be kept much lower... just like saltwater reef tanks. For this reason, tanks that need very little to no nitrates often use media that has anaerobic properties. This means that a 3rd strain of BB can live deep inside... a strain that can survive with zero oxygen, or anaerobic. This strain of bacteria is capable of reducing nitrates.

Speaking of nitrate reduction, you will see people talking about skimmers and refugiums. You don't need to worry about either of these right now. All you should know is anaerobic bacteria, skimmers, and refugiums all are for the reduction of nitrates... and possibly phosphates, both of which should be kept low with corals in a tank.

Converting ammonia to nitrites, and nitrites to nitrates is your cycle. When a part of the system is lowering nitrates and phosphates, the general term is nutrient reduction.

Phew... are you still with me? So, the difference in saltwater is that we have porous rocks in the tank, and beneficial bacteria will colonize it. That BB will hold our cycle, but it will not perform nutrient reduction, which is why we use media like Seachem Matrix, and/or have refugiums and/or skimmers. When BB colonizes rock, we call it live rock. Mature live rock will also contain many other forms of life, such as tiny bug looking things called pods, coralline algae, and feather duster worms to name a few. Live rock may also contain pesty critters that you might not want in your tank.

Also on this subject... ammonia, nitrites, nitrates, phosphates, calcium, alkalinity, and magnesium, pretty much anything that you test for and even the things you don't. These are your parameters. There are many sources online that will tell you where you want your parameters for calcium, alkalinity, and magnesium, but you may not need to worry about that yet. You will need test kits for ammonia, nitrite, nitrates, and pH from the moment water hits your tank. You'll use the first three to cycle your tank and make sure it stays cycled, and it's always a good idea to keep an eye on pH to make sure it is remaining at a stable level. API is a common brand of test kits, but I prefer Salifert.

I would suggest that you start with a FOWLR (fish only with live rock) tank. Corals are sensitive creatures, but fish and live rock are less so. Without corals, you will not need to worry about testing for calcium, alkalinity (which is the same as KH), or magnesium. You also will not need to worry about maintaining nitrates at a very low level. Start with a FOWLR and learn to maintain the tank at an easier level before stepping up to the more involved stuff. This is a great way to learn as you go.

So, to answer your other questions about the guide...

Rock type - I would get BRS (Bulk Reef Supply) reef saver rock. This is a highly porous type of dry rock, but it will become live rock over time in your tank. It is easy to work with, guaranteed pest free because it's dry, and you don't need to cure it. More on curing rocks later if you want... I'd suggest you get the reef saver rock so you won't have to worry about it.

Corals and their cost and difficulty levels - As mentioned, corals are more sensitive to parameters, and you will have to buy and perform twice as many tests. Corals themselves are kinda spendy, so they definitely add to the cost. The biggest single cost may very well be a reef light. This is the other reason I recommend that you start with a FOWLR. One of my biggest pieces of advice is to save your pennies until you can get the best light that your budget allows. The last thing you want to do is buy reef lighting twice... I did that. It stinks to buy one light that isn't all that cheap, find that it will not do for your needs, so have to invest in another one in the near future. I replaced my reef light within the first year and wish I had never spent the money on that first light.

However, corals are quite rewarding. Once you get the cost of a reef light out of the way, you can purchase corals at your own price point and in your own time. I certainly didn't get all of my corals in short order, so the cost has been much easier after all the initial purchases.

Sorry, but I would not put four fish in a 15g, but you could replace the clown goby with the tail spot. In general, you do not want a goby and a blenny unless you have a very large tank where they can have their own territories. Some gobies are bottom dwellers, but the clown goby is a rock/coral dweller. They will not get along but will need to occupy the same space in your tank. I do think you need to stick to 3 fish anyhow, because 4 may put too much of a bioload on your tank. Bioload meaning the amount of ammonia and waste they'll produce, and food they'll need... all of which will mean maintaining your parameters for ammonia/nitrite/nitrate/phosphates will be more difficult.

Also, a very important thing with stocking - You must stock your least aggressive fish first and give it time to get comfortable before introducing anything more aggressive than it is. In your case, you'll want the goby or blenny first. Give him about a month to be sure he's comfortable, healthy and eating, then introduce the clowns.

It's a lot, I know. Start slowly with rock, substrate, (which is your sand) and how you'll provide water, cycle the tank and move on to inverts and fish from there.

 

Very good breakdown of equipment and a great addition to the info on cost by Lorekeeper. I also agree that RedSea makes better test kits for reefing. My particular preference is.

API for ammonia and nitrites, because it works and it's cheaper.

Salifert for pH, and I prefer this brand for testing nitrates in freshwater tanks. API is frustrating and hard to read, making it less accurate.

RedSea for saltwater nitrates when you want an accurate low reading for a reef tank. Also RedSea for phosphates, calcium, alkalinity and magnesium.

If you will start with a FOWLR, I would recommend getting API for ammonia and nitrites and Salifert for pH and nitrates. This is the most cost effective way I've found to get the accuracy I want.