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Hi all... I was just wondering if I could use my 20 gal. and change it into a saltwater aquarium... is it too small??? and is a saltwater aquarium much harder to take care of?? I've never owned a saltwater tank.. i have been keeping freshwater for 2 years.

any help and/or comments would be greaty appreciated.. thank you!

it is possible, but exspecially for your first saltwater you would want a bigger tank. more like something 50+ gallon

For SW you will need to monitor the tank much more closly. Smaller tanks such as a 20gal will need to be topped off daily. Even small changes in the water can make a big change in the quality. Larger tanks have a better buffer. 55gal tanks make for a good starter tank as far as size is concerned. But to answer yoru question, yes, a 20gal tank will work. The draw backs are, more work, and a much lower stocking level. Only 2 or 3 fish.



Dan

My 20g is working out fine for a simple fowlr setup. If I get the lighting tweaked a little more I want to add some corals. You can fit 2-3 small fish(~2) in a 20g. I'm doing just neon gobies right now but plan to stock it with a tailspot blenny and firefish when I manage to find the tailspot.

Ok..thank you all for your help.. I will think about it..I currently have two JD's in a 60 gal.. so maybe when those die off in a long time....i'll be more experienced in fish keeping and I'll switch it to a SW./:'

One further piece of advice to hand out here is this.

Quite a few people who make successful freshwater aquarists come to grief when trying saltwater. The reason is quite simple.

Freshwater aquaria are, in the main, much lower maintenance than saltwater aquaria. This is because of the BIG difference in the capabilities of freshwater and saltwater fishes to cope with water chemistry changes.

Freshwater fishes, in the main, have evolved to live in environments where the water chemistry is subject to change due to natural forces - rainfall being a major actor in these environments. There are seasonal changes to take into account (difference between wet and dry seasons in the tropics), and also more local changes caused by the sudden appearance of a heavy rainfall over the river or lake where the fishes live. Add to this that rainfall washes material into the watercourse from surrounding land, and the picture is one of a fairly dynamic environment. Freshwater organisms, fishes included, have evolved the osmoregulatory machinery to cope with these changes, which is why they can, in the main, cope with changes in an aquarium, provided those changes are not too large or involve toxic substances such as ammonia.

Saltwater fishes, particularly those from coral reefs, lack this adaptability. Principally because they have evolved in an environment where it isn't needed. If you think that the water volumes of rivers and lakes are huge in comparison with a freshwater aquarium, then the ocean is several magnitudes larger again. The composition of seawater around a coral reef is remarkably stable, and because that seawater varies so little in composition with the passage of time, saltwater fishes don't need the additional complication of osmoregulatory machinery to cope with large scale water chemistry changes - it's an energy expense that they can better devote elsewhere. In fact, the constitution of coral reef seawater has changed precious little in something like 50 million years, and in terms of water chemistry, the coral reef is one of the stablest environments on the planet. Small wonder that coral reef fishes are far more e to expiring in the aquarium, given that even a large aquarium provides scope for water chemistry changes many times larger than those fishes would ever encounter in the wild. Indeed, it's eloquent testimony to how far the marine hobby has proceeded that we CAN keep coral reef fishes and invertebrates alive for timespans of a decade or more!

Doing this, however, requires that the aquarist be MUCH more actively interventive in the aquarium. Water quality has to be monitored with rigorous attention to detail, and action taken the moment parameters start to drift outside of a pretty narrow acceptable band. You have far less margin for error in a marine aquarium, ESPECIALLY with respect to those two BIG killers, ammonia and nitrite, whose toxicity in alkaline sea water is considerably greater than in a soft, acidic freshwater aquarium to start with. Basically, you have to be prepared to nail ammonia and nitrite down to ZERO and invest lots of money in the technology to allow you to do this, and once that's in hand, you then have to be prepared to monitor a much wider range of other parameters than you would have to in freshwater. In a planted freshwater aquarium, nitrates are taken care of by a combination of the plants and regular water changes. Unless you have a macroalgae refugium among your management tools, you have less scope for nitrate management without some fairly expensive filtration technology, and nitrates need to be managed more assiduously in the marine environment because many marine fishes tolerate far lower nitrate values than freshwater fishes. While you may be able to get away with 40ppm of nitrates in a freshwater aquarium, anything above 10ppm in a marine aquarium is not good in the long term, especially if you're keeping fishes such as Chaetodon Butterfly Fishes or Pomacanthus Angels. Then, if you're keeping corals, I'm reminded of something that was said by David Sxaby when his monster reef aquarium was reviewed in Practical Fishkeeping - his view is that if you want good coral growth, keeping on top of phosphates is, if anything, even more important than keeping on top of nitrates. Then, you have the fun of managing trace elements (something only hardcore Discus breeders have to worry about in freshwater). If you decide to keep corals, you have calcium management to throw into the mix too.

If the above all sounds frightening to you, don't worry. Thousands of people do this successfully around the world. You just have to know in advance what your workload is likely to be, what you will have to do to be successful, and prepare yourself for that workload, both physical and intellectual - not only is shifting buckets of seawater around physically arduous, but doing the management calculations involves a fair amount of headwork. Just make sure you go in to the enterprise with your eyes open, do LOTS of research beforehand, and remember that what I said in freshwater forums about a few hours' research before a penny is spent paying dividends applies at least ten or twenty fold to marine fishkeeping. Ditto the bit about patience.

Some people jokingly refer to saltwater fishkeeping as "The Dark Side" (in allusion to the Star Wars movies). I presume in part because the technology bolted on to your aquarium makes it look like the internals of the Death Star. However, if you do the spadework and the headwork, it's anything but dark - a successful marine aquarium is a supernova blast of intense colours you'll be hard put to find outside of a movie company's special effects department! Sit and think hard before jumping in, and make sure your eyes are open when you do, but if you decide you're ready, and you've done your spadework beforehand, it can be VASTLY rewarding.


Panda Catfish fan and keeper/breeder since Christmas 2002

I don't completely agree. A well setup fowlr tank is not that much work especially after it's been established for many months to a year. I've got a heck of alot more junk hanging on my planted tanks with co2 injection than my 20g. There's only a cpr refugium on the back and a powerhead inside the tank. Being a small tank with no form of mechanical filtration my 20g does require weekly water changes but so do all my freshwater tanks. So far this tank has been more expensive and required more research but is by no means more difficult and is actually giving me far less headaches than any of my freshwater planted tanks. Unless you find mixing salt difficult maintaining my 20g saltwater tank is no more difficult than maintaining my 5g freshwater shrimp only tank.

Now if we're going for the ultimate corals, most sensitive fish, or a heavily stocked tank or comparing it to a tank full of the hardiest freshwater fish where you can allow the nitrates to reach 60ppm without noticing any decline in fish health then yea it is more work and the term heavily stocked has an entirely different meaning in saltwater tanks. Saltwater is also definitely more work to setup and longer to setup but provided you have patience once setup you can step back and just do basic maintenance. Clean out the skimmer if you have one and do water changes although I'm told larger tanks don't require water changes very often compared to my nano. The most difficult part of keeping my tank is remembering to add a scoop of ro water from the nearby container for top offs every other day.

Oh, once a marine aquarium has settled and is in a relatively stable state, then the amount of intervention required isn't as high obviously. The point of my post, apart from highlighting important differences between typical freshwater environments and the marine environment, was to prepare the groundwork for starting a marine aquarium, which is a considerably more intense process than starting a freshwater aquarium. A marine aquarium, in general, requires a higher initial capital outlay (because there is more technology involved), more time to mature the aquarium, more attention to detail during the initial setting up (more frequent water testing etc), and much more care and attention to stocking details, because mistakes in this regard are more expensive.

However, if you're careful, diligent, patient and willing to learn, you can, in time, have a truly spectacular looking aquarium up and running. It does, however, take more effort to reach that point than a freshwater aquarium requires. I don't think many marine keepers will disagree with that.


Panda Catfish fan and keeper/breeder since Christmas 2002