I would like to start a saltwater tank but am limited on space. I've kept freshwater successfully for a while and know that they can be quite different. All i have available right now is a 20 gallon tank. i know there arent many saltwater fish that can be kept in a 20, and larger tank size is better. I was thinking of just doing an invertabrate tank. Would this work? For filtration i have an aquaclear 20 and 30 on hand but may be able to get something larger. I know protein skimmers are needed and can get a hold of one fairly cheaply. Besides a substrate, filters, and a protein skimmer what else do i need? Instead of corals could i just go with live rock? What species of inverts would work in a 20? and what are some good sites or books with info on saltwater invertabrates? Thanks in advance
20 gal saltwater tank?
- Thread starter redwing191
- Start date
I'm guessing you want mobile inverts, like shrimps and crabs. You can have a tank that small, and it is more work--closer to keeping a heavily planted, high light, CO@ injection, daily ferts tank. 
But: here's what I would do.
Put in about 1-2 inches of sand. Pool sand, play sand, whatever. Add 15-20 pounds of good live rock--stuff that has lots of interesting critters and colors. Keep the tank this way for about 2 months--this will get you used to topping off for evaporation, cleaning, etc. Then, start adding some smaller inverts, like snails, tubeworms, maybe a few crabs, and some shrimp. You'll want to pick these carefully, as not al are created equally. I'd go with emerald crabs and cleaner shrimp. A variety of snails will be fine, though- cerith, nasarrius, turbo--all are okay.
If this is still doing well in 6 months, consider adding a small blenny or goby. I've found that the hardest part of the smaller tanks isn't getting stock, it's keeping them stable. Going slow will make this easier, since you can monitor and see what needs to be automated, and how often maintenance is needed.
But: here's what I would do.Put in about 1-2 inches of sand. Pool sand, play sand, whatever. Add 15-20 pounds of good live rock--stuff that has lots of interesting critters and colors. Keep the tank this way for about 2 months--this will get you used to topping off for evaporation, cleaning, etc. Then, start adding some smaller inverts, like snails, tubeworms, maybe a few crabs, and some shrimp. You'll want to pick these carefully, as not al are created equally. I'd go with emerald crabs and cleaner shrimp. A variety of snails will be fine, though- cerith, nasarrius, turbo--all are okay.
If this is still doing well in 6 months, consider adding a small blenny or goby. I've found that the hardest part of the smaller tanks isn't getting stock, it's keeping them stable. Going slow will make this easier, since you can monitor and see what needs to be automated, and how often maintenance is needed.
Thanks for the response. Yeah i am interested in mobile invertebrates. I was planning on going slow with it. About how often and how much water should I change with a water change? Other than monitering it and water changes are there any other fairly regular maintance procedures besides cleaning the filers?
Topping off with FW--may be a daily task, maybe every other day. Tracking the salinity is really important in small systems. Cleaning the glass--especially initially, most likely weekly at least. I'd plan on doing at least one water change weekly--especially initially. Target changing about 4-5 gallons each time, but be flexible with this. If things seem to have problems, more water changes will be good.
Can i just take my aquaclear filters, clean them out with hot water and use them on the saltwater tank? I assume i would have to get new carbon and mechanical media.
I have a 20 gallon salt water tank.... as far as maintenance goes it's a pain in the butt! Smaller tanks really are a lot of work.. everything seems to happen much quicker!
Here's what I did to get it started:
I put in
- 1.5 inches Carib Sea Aragamax mixture (sand, coral particle and argonite mixture)
- 20 pounds live rock
- filled it up with salt water and turned on the powerhead, heater and hob filter for water movement...
Within 8 weeks I had an algae outbreak, so I added nasarius snails and hermit crabs.... I left it like that for anoter 3 months before I started adding soft corals and other inverts.
I do a 25% water change (with pre-mixed salt water) once a week.
I also top up the tank with fresh water every 2 days...normally I lose an inch every 2 days (in the summer I have to top it up daily). I also have to clean the glass 2-3 times a week.
When something goes wrong, there is very little time to react with a small tank. My 20 gallon is a lot more work than my 90 gallon - I spend twice as much time a week working on it!
Here's a really horrible example of how quickly things happen in smaller tanks... I normally use bottled water for my tanks because there is too much crap in my tap water. Last September the evaporation rate was still really high and I didn't have a chance to get more water, so I decided to use my tap water and just boil it then use de-chlorinator.... I topped up my 20 gallon and my 90 gallon, both needed about a 10% top up....and within 1 hour the 20 gallon tank was visably in trouble! My star fish were exploding from the inside out, my clownfish were laying on their sides! There was nothing happening in my 90 gallon tank, so it took me about 2 days to figure out what the problem was.... In the end I lost EVERYTHING in my 20 gallon (hermit crabs,clownfish, scooter, red algae corals, brittle stars, snails etc etc).... I pretty much had to start that tank all over again! I even had to replace my substrate and re-cure my live rock (which took longer this time because it took about 9 weeks for all the copper to leach back out of the rock)..... The only damage in my 90 gallon was two hermit crabs.
As soon as I knew what the problem was, I did a 70% water change on both tanks.
Anyway, I'm not trying to get you to forget the idea of a 20 gallon tank, I just want you to be aware of how much work they are. Be prepared to have to do somthing to it every 2-3 days! But with lots of care and attention on your part, you could really have a beautiful setup!
Good luck!
_Decz.
p.s. as for your aquaclear filters.. if these have been used in a freswater tank, you will need to throw them out and start fresh. If you plan on using a filter/sponge in your salt water setup and it gets too dirty, you can rinse it in a bucket of salt water -- I use the water that I just drained during water changes so that I don't waste anything.
Here's what I did to get it started:
I put in
- 1.5 inches Carib Sea Aragamax mixture (sand, coral particle and argonite mixture)
- 20 pounds live rock
- filled it up with salt water and turned on the powerhead, heater and hob filter for water movement...
Within 8 weeks I had an algae outbreak, so I added nasarius snails and hermit crabs.... I left it like that for anoter 3 months before I started adding soft corals and other inverts.
I do a 25% water change (with pre-mixed salt water) once a week.
I also top up the tank with fresh water every 2 days...normally I lose an inch every 2 days (in the summer I have to top it up daily). I also have to clean the glass 2-3 times a week.
When something goes wrong, there is very little time to react with a small tank. My 20 gallon is a lot more work than my 90 gallon - I spend twice as much time a week working on it!
Here's a really horrible example of how quickly things happen in smaller tanks... I normally use bottled water for my tanks because there is too much crap in my tap water. Last September the evaporation rate was still really high and I didn't have a chance to get more water, so I decided to use my tap water and just boil it then use de-chlorinator.... I topped up my 20 gallon and my 90 gallon, both needed about a 10% top up....and within 1 hour the 20 gallon tank was visably in trouble! My star fish were exploding from the inside out, my clownfish were laying on their sides! There was nothing happening in my 90 gallon tank, so it took me about 2 days to figure out what the problem was.... In the end I lost EVERYTHING in my 20 gallon (hermit crabs,clownfish, scooter, red algae corals, brittle stars, snails etc etc).... I pretty much had to start that tank all over again! I even had to replace my substrate and re-cure my live rock (which took longer this time because it took about 9 weeks for all the copper to leach back out of the rock)..... The only damage in my 90 gallon was two hermit crabs.
As soon as I knew what the problem was, I did a 70% water change on both tanks.
Anyway, I'm not trying to get you to forget the idea of a 20 gallon tank, I just want you to be aware of how much work they are. Be prepared to have to do somthing to it every 2-3 days! But with lots of care and attention on your part, you could really have a beautiful setup!
Good luck!
_Decz.
p.s. as for your aquaclear filters.. if these have been used in a freswater tank, you will need to throw them out and start fresh. If you plan on using a filter/sponge in your salt water setup and it gets too dirty, you can rinse it in a bucket of salt water -- I use the water that I just drained during water changes so that I don't waste anything.