25 gallon tank?


Reefing newb
Hi, i have i have a 25 gallon tropical fish tank and i was looking to convert it into a saltwater aquarium. Is this big enough and if so what kind of fish are good for beginners?

for a beginner in saltwater you really wanna go has big as you can afford because the bigger the system the easier it is to keep the water parameters stable and in good condition.
I agree with dustin, I started with a 14g nano and had some problems in the beginning. I had good luck with clowns
It can be done with a 25 gallon tank, but it won't be easy. As others have pointed out, the smaller the tank, the more difficult it is to maintain water parameters. In a 25 gallon tank, you will be limited to 2 to 3 small fish. Clowns are a good starter fish, as are firefish, gobies, chromis and blennies.
Although it kinda goes against the typical train of thought, a small tank isn't always harder than a large tank. A lot depends on what you want to keep in it. I had a ten gallon tank for two years with just a few pounds of live rock and two yellow tailed damsels.

I recommend considering what you want to keep. Then, purchase a tank **at least** large enough for what you want to keep. Keep in mind that you may very well want more or larger items down the road.
My suggestions are - yellow watchman goby and/or a blenny (bicolor, lawnmower, scooter - they are all awesome).

My friends have had good luck with their nano (no sump or refugium), but they take very very good care of it - I think is is 14 gallons or so? 25 gallons is much bigger in that respect.

Just take your time on adding livestock/coral. Regular water changes are a must!
Hi Coolie,

I converted a 30g tropical fish tank to a reef tank. It took some time and preparations however. My 30g tank has 10 coral pieces, liverock, live sand, a clownfish pair, bluefin wrasse and starry blenny.
I upgraded the light to (2) 65w power-compact bulbs in a coralife fixture, added a hang-on-back skimmer from Octopus and I have an Eheim canister filter which I use for adding flow & filter media such as carbon. I also have a Koralia 1 powerhead for additional flow.

After adding all this equipment, the conversion was quite expensive.

I noticed petco had a 29g BIOCUBE aquarium for $299.00 in the store (you can find it cheaper online too).
This tank has the "small" factor to help you adjusting into Saltwater keeping, but it also incorporates a lot of the filtering / lighting you will need anyway. I believe the only thing you will need to add to this tank is a skimmer.
An all-in-one nano reef such as the BIOCUBE or RED SEA MAX might be a good choice for you and you can use the 25g as a quarantine tank.....

If you're up for it, you could do a 55g (find a pre-drilled one if you can) and use the 25g as the sump system.....do your research though and take your time.

Everyone on this site has great experience and will help you with any questions you have.

Good luck to you....post some pics when you get going!
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not too much to add the pack has pretty much covered the bases

however, i have 90 gallon and im ready to go bigger, and its been less than a year, ive been looking for a 180 or bigger

in regards to 55 gallon tanks, they are a dime a dozen on ebay and craigs list, and a 55 is a good starter size

either way, ask all the questions you can, especially on this site
the people are very knowledgeable, and questions dont cost anything, mistakes can cost alot

I love my 25. I think it's one of the "perfect" sizes: small enough to be big, but still small enough to be small.

I might get yelled at for this, but I've never thought that smaller tanks are any more work than much larger tanks. If anything, a 90 or 120 will be more work, and more to worry about. I run my 25 with no sump or fuge, with just a HOB skimmer and a powerhead. A skimmer - even a mediocre one - is a must. I have lots of live rock and a deep sand bed. It's been up and stable for two years, and everything is happy. I get consistent 0/0 on nitrate and ammonia.

I don't believe that I do anything any better than any other reefer, and I definitely don't have a "magic touch." So, I say get a 25 to your heart's content. Just be mindful of your bio-load, and change a few gallons every couple of weeks. Small tanks are easy as pie - as long as you stay within their limits! Overdo it and you'll be paying for it, literally.

Also, I recommend staying away from aquapods and the like. You can build your own system for about the same amount of cash - maybe a little more. And, you'll have better flow control and more options as far as skimmers go. This is really just a personal opinion. Most people that have them really like them...BUT, they all come with PC lights, I think, and after switching to T-5s I'll never go back.

I also suggest going for T-5 lights. They're far superior to PCs in my opinion, and I've seen excellent growth from my SPS, LPS, and softies under T-5 lights.
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It can absolutely be done is you have the willingness & consistency. Since the tank is small, like everyone said, it will go thru changes faster. I suggest doing more frequent water changes (x2 per week) on top of having a good skimmer, sump and live rock. You should be ok.