Which type of hydrometer is more accurate?

[TheChad]

Hey All,

My wife and I just started our first saltwater aquarium. We have a 29-gal tank, and we mixed our instant ocean mix at 28-gal. We took our sample into the LFS and was told our salinity was too high 1.028. So I bought the Instant Ocean Hydrometer so i could test this my self. After exchanging about 4-6 gallons of water, I get a reading of 1.023.

When I took my water sample in to another LFS to get our damsel's, they told me my salinity was 1.20 which they was was perfect.

I know its only a 0.03 difference, but if thease fish are as sensative as I understand that they are, that might make a difference.

My Instant Ocean Hydrometer is the floating needle type, the one they used at the 2nd LFS was the floating thermometer type..

Is one more accurate than another?


Right now we just have 2 damsels, one blue and one yellow tail. Once our tank cycles (Which I'm told is usually once the algie grows, and turns from brown to green (1-2 Months), We will be looking at getting a couple of clown's, a fire shrimp, probably a choclate chip star fish, a Heniochus Butterfly, and a spotted mandarin. We also wanted an anemone for our clowns, but I am getting mixed input of weather or not it would be successfull in our tank!?

Thanks for the help!

-TheChad

 

[dskidmore]

Salinity:
A) Glass floating hydrometers are usually more accurate than plastic swing arm ones. Refractometers are more accurate than either, and some are self-correcting for temperature.

B) All hydrometer readings should be corrected for temperature.

C) Stability is more important than an exact number. Make corrections slowly.

Cycling:
A) Whoever advised you to buy the damsels to cycle the tank has not been studying modern techniques. Damsels will cycle the tank, but may suffer permanent damage, and can be very aggressive towards other fish you may want to add later.

B) Algae is a decent indicator of the later stages of a cycle, but the best way to track it is with ammonia, nitrite and nitrate test kits. You should see ammonia rise then fall, nitrite rise and fall a bit delayed from the ammonia curve, and nitrate keeps rising. At the end of your cycle you should see ammonia 0, nitrite 0, and decently high nitrate. You are then ready for a big water change and the addition of one fish.

Stock Selection:
A) Clowns are great starter fish. Go for it! They do not require an anemone to be happy contrary to popular belief.

B) Shrimp and star fish are decent inverts to have. You might fist want to add snails and hermit crabs to keep your aquarium clean. Add you "cleanup crew" after your cycle is over. Don't be surprised to see some carnage, most hermit crabs will fight with each other, and pick on the snails. They do their job well though.

C) Keep in mind that butterfly fish will require a 50+ gallon tank when he is full grown. (not counting the space the other fish take up.) Unless you are planning to upgrade, you might want to stick to fish that do not grow as large, like the Royal Gramma, or something from the goby family.

D) I'm afraid the mandarin is not likely to survive. He primarily eats the small critters that grow on live rock, and requires a rather extensive, mature collection of live rock to keep him going. Even experienced aquarists can have trouble with this fish.

E) You could have an anemone, but not right away, and not with default equiptment. You need to research the kind of more intense lighting required for reef aquariums, as anemones live partially off of sunlight. They also require very stable water, so wait 6 months or so for everything in your aquarium to stabilize before you get it. If you set up the conditions properly for an anemone, you can also keep some of the easier corals.

 

[SkinnyPete]

It is well, WELL worth the money to buy a refractometer.

You can get cheap ones now for like $30-$40. I was running my tank for 6 months at, what I thought was, 1.024 - my desired reading. I noticed that my Calcium was high (not a big deal) and was wondering if my hydrometer was wrong. I brought it to a lfs and had it tested on a refractometer that read 1.029! I bought another hydro (now I had both the float and the arm type). They both read at 1.024, but after getting it tested at 1.029 at a DIFFERENT lfc, I decided to by a refractometer. I had already wasted money on two hydrometers. Over the course of about a month, I slowly lowered my sg from 1.029 to 1.024. I ignored the warnings on these forums because I didn't want to spend the money - but, the hydrometers are just unreliable. I would suggest to do what you have to do to buy a refractometer. Even if it means putting off a fish purchase for a month or so.

- Skins

 

[Brenden]

I agree buy a refractometer. If that is not in the budget have your water tested by someone that has one and compare the reading to the reading you get on your hydrometer. That way you will know what the reading really is.

 

[tecwzrd]

No one has said it yet so I guess I will, your planned fish load is excessive for a 28 gal tank IMO. The calculator at the top of the page:
http://www.aquariumadvice.com/calcs2.php?type=fishcapacity

Recommends 5” of fish minus the tail. That means your 28 gal is enough for 1 clown and 1 smaller fish like a fire fish or Pseudochromis. Also that assumes taking out the fish you currently have in there. While you can overstock a tank it usually leads to disasters down the road and requires an excellent filter & skimmer.

A spotted mandarin is a very difficult fish to keep. The spotted mandarin is fairly cheap but needs a well developed reef system that is about a year old to survive. Read more in the links below.

An anemone is not necessary for tank bred clowns and unless you have adequate lighting I wouldn’t get one.

Doing a small weekly PWC is your best bet in not upsetting your tank as far as SG goes. The floating hydrometer is ok for FOWLR but if you plan on keeping corals I’d get a refractometer along with MH/PC lighting.

Lastly checkout the book section on this site and read up on the hobby more before jumping in too deep. I’d highly recommend asking about a fish/invert on this site before wasting your money on something that might not work or worse die.
http://www.aquariumadvice.com/saltbook.php

Spotted Mandarin
http://www.liveaquaria.com/product/prod_display.cfm?pcatid=554&N=0
http://animal-world.com/encyclo/marine/goby_ble/psychedelic.php

Heniochus Brown Butterflyfish (this fish grows to 8”!)
http://www.liveaquaria.com/product/prod_display.cfm?pcatid=246&N=0

True Percula Clownfish
http://www.liveaquaria.com/product/prod_display.cfm?pcatid=756&N=0

Firefish
http://www.liveaquaria.com/product/prod_display.cfm?pcatid=171&N=0

Royal Gramma Basslet
http://www.liveaquaria.com/product/prod_display.cfm?pcatid=53&N=0

Fridmani Pseudochromis
http://www.liveaquaria.com/product/prod_display.cfm?pcatid=162&N=0

 

[Brenden]

8O I did not pay attention to the tank size. As tec said your fish list is way off. Even though the links say a mandarin needs a 30 gal tank that is not a good idea unless you regularly dose your tank with pods or have a nice size fuge.

 

[Lagger]

Maybe I missed it in the pic, but what are you using for filtration? I also can't see a heater in there but see the thermometer. Also, ditch the bubblewall and get a powerhead.

Peace_

 

[TheChad]

No one has said it yet so I guess I will, your planned fish load is excessive for a 28 gal tank IMO. The calculator at the top of the page:
http://www.aquariumadvice.com/calcs2.php?type=fishcapacity

Recommends 5” of fish minus the tail. That means your 28 gal is enough for 1 clown and 1 smaller fish like a fire fish or Pseudochromis. Also that assumes taking out the fish you currently have in there. While you can overstock a tank it usually leads to disasters down the road and requires an excellent filter & skimmer.

You are saying you can only have 2 small fish in a 29 gallon tank? That doesn't seam right!? I was under the impression it was one small fish for every 5 gallons, and all the LFS have said you could have 1 large fish.

I am not saying you are wrong, i'm just asking because 2 small fish for a 29 gallon tank just seams a little crazy...


Thanks,

-TheChad

 

[TheChad]

Maybe I missed it in the pic, but what are you using for filtration? I also can't see a heater in there but see the thermometer. Also, ditch the bubblewall and get a powerhead.

Peace_

The filtration is an under gravel filter, which the LFS said was better than a top mounted filter, like the bio wheel I was going to get.

The heater is behind the pink silk plant in the center, we placed the plants to hide the 'ugly' parts of the tank...

The LFS also advised me that the Powerhead wasn't nessary unless you had a reef, we are only going to have a fish-only setup (For now, eventually when we learn more about saltwater fish, and we build a home, we are going to get a MUCH larger in-wall type tank Reef Tank)

Thanks for the help,

-TheChad

 

[TheChad]

Salinity:
A) Glass floating hydrometers are usually more accurate than plastic swing arm ones. Refractometers are more accurate than either, and some are self-correcting for temperature.

B) All hydrometer readings should be corrected for temperature.

C) Stability is more important than an exact number. Make corrections slowly.

Cycling:
A) Whoever advised you to buy the damsels to cycle the tank has not been studying modern techniques. Damsels will cycle the tank, but may suffer permanent damage, and can be very aggressive towards other fish you may want to add later.

B) Algae is a decent indicator of the later stages of a cycle, but the best way to track it is with ammonia, nitrite and nitrate test kits. You should see ammonia rise then fall, nitrite rise and fall a bit delayed from the ammonia curve, and nitrate keeps rising. At the end of your cycle you should see ammonia 0, nitrite 0, and decently high nitrate. You are then ready for a big water change and the addition of one fish.

Stock Selection:
A) Clowns are great starter fish. Go for it! They do not require an anemone to be happy contrary to popular belief.

B) Shrimp and star fish are decent inverts to have. You might fist want to add snails and hermit crabs to keep your aquarium clean. Add you "cleanup crew" after your cycle is over. Don't be surprised to see some carnage, most hermit crabs will fight with each other, and pick on the snails. They do their job well though.

C) Keep in mind that butterfly fish will require a 50+ gallon tank when he is full grown. (not counting the space the other fish take up.) Unless you are planning to upgrade, you might want to stick to fish that do not grow as large, like the Royal Gramma, or something from the goby family.

D) I'm afraid the mandarin is not likely to survive. He primarily eats the small critters that grow on live rock, and requires a rather extensive, mature collection of live rock to keep him going. Even experienced aquarists can have trouble with this fish.

E) You could have an anemone, but not right away, and not with default equiptment. You need to research the kind of more intense lighting required for reef aquariums, as anemones live partially off of sunlight. They also require very stable water, so wait 6 months or so for everything in your aquarium to stabilize before you get it. If you set up the conditions properly for an anemone, you can also keep some of the easier corals.

Thanks for the info! This was very helpfull

-TheChad

 

[Brenden]

There is not a cut/dry rule for fish. It depends on the type of fish and bioload they produce. The most I would probably put in a 29 is a pair of clowns. The small fish per 5 gal is way off.

 

[TheChad]

Brenden,

You said 2 clowns for fish, would I still be able to put the fire shrimp, and the chocolate starfish, or are you suggesting 2 clowns, and 2 clowns only?


P.S. Is there another type of fish that looks similar to a butterfly or angel fish, but that is of a smaller type?


P.P.S. How long would it take for a butterfly fish that is about the size of a silver dollar to become full grown?


Thanks,

-TheChad

 

[dskidmore]

You are saying you can only have 2 small fish in a 29 gallon tank? That doesn't seam right!? I was under the impression it was one small fish for every 5 gallons, and all the LFS have said you could have 1 large fish.

I am not saying you are wrong, i'm just asking because 2 small fish for a 29 gallon tank just seams a little crazy...

The general rule is 5 gallons for each inch of full grown fish. (Unless you're counting on fish death or aquarium upgrades, you need to count the full grown size rather than the current size.)

True Percula Clownfish, among the smallest clownfish, can grow to 3" at adult size. Thier social order affects thier growth, so with a pair of clownfish, you end up with a bit less than 6" of fish. Multply by 5 gallons per inch, and you've already filled your 29 gallon tank.

Between the fact that saltwater does not hold oxygen as well as fresh water, and the average saltwater hobby fish being larger than your average freshwater hobby fish, this drasticly cuts into the total number of fish you can have.

The good news is that there is a large variety of interesting invertabrates you can try. Many of them are scavengers, so they don't affect your bioload as much as fish do.

With careful management, you can break the gallons of water per fish rule, but this is not recomended for beginners. If your Local Pet Store accepts trade-ins, you can also consider turning in extra fish when the population starts outgrowing the tank. (Not advised for those that get emotionally attached to thier fish.)

 

[tecwzrd]

Brenden,
You said 2 clowns for fish, would I still be able to put the fire shrimp, and the chocolate starfish, or are you suggesting 2 clowns, and 2 clowns only?
P.S. Is there another type of fish that looks similar to a butterfly or angel fish, but that is of a smaller type?
P.P.S. How long would it take for a butterfly fish that is about the size of a silver dollar to become full grown?
Thanks,
-TheChad

Chad, the lfs was probably referencing the 1 small fish per 5 gal rule to FW, not SW. FW fish are much more tolerant to less than perfect water conditions because they often come from less than perfect water conditions in FW lakes hence the biological advantage they have over SW fish.

I kept 6 large fish (7+” cichlids) in my 55 gal for years without any trouble but SW fish come from the ocean (unless tank bred) which has very exacting water parameters ie: PH around 8.2, average salinity of the ocean is 35 PPT, and SG of 1.025.

That is one of the main reasons why it’s recommended to keep less fish than FW in a SW tank because with a 28 gal tank your water parameters can go south very quickly with a large bio load (lots of fish). Also SW fish are used to huge environments and cramming a ton of fish into a small tank will lead to a ton of stress and sickness for your fish.

The bio-wheel would have been a better option then the UGF and about 35 lbs of LR would be better then either as far as filtration goes.

I’d still ditch the air wand and get a PH as Lagger said because it does very little in moving the water which you need to keep your tank properly aerated. I assume you already have one PH hooked up to your UGF and if it’s rated at 295 GPH and disturbing the surface of the water you should be ok for now. If not I’d add another PH at the other end of the tank.

Personally in such a small tank I wouldn’t get any Angels or butterfly fish. There are lots of fish that are colorful that don’t get too large and are not too aggressive. I’d look through this site http://www.liveaquaria.com/product/scateg.cfm?pCatId=1926 for fish that max out around 3 to 4”, are skinny (not fat and 3”) and are listed as an “easy” fish to start out with. As said before I wouldn’t get any more than two of these types of fish until you upgrade to a larger tank. Clowns can be fun but if you do get a pair then I’d make sure they are “tank raised” as feeding them will be easier then “wild caught” You can still get the starfish and shrimp but I’d wait at least 6 months to make sure your system is stable.

If you haven’t invested in a RO\DI unit yet I’d recommend it highly as you will have much better success with your SW fish and because your tap is likely contaminated with harmful chemicals (not just chlorine) Checkout this site to see what your water parameters are. http://www.ewg.org/tapwater/yourwater/

For cheap RO\DI units check ebay for some great units around $100.00
http://stores.ebay.com/Filter-Direct-store
http://stores.ebay.com/ROfilterDepot

Angels & Butterflies reach full size in anywhere from 2 to 4 years depending on tank size & feeding habits. Don’t believe the myth that keeping a large fish in a small tank will keep him from getting large. All it will do it create stress and sickness for the fish as it grows. My Yellow Tang has already grown an inch larger in just 4 months.

Make sure you feed your SW fish a well rounded diet of frozen like SFFB Marine Cuisine
http://www.sfbb.com/frozen.asp & Ocean Nutrition Formula one & two frozen and flake.
http://froogle.google.com/froogle?q=Ocean Nutrition

Both brands should should be available at your lfs.

Lastly make sure you acclimate all your SW fish or other animals preferably for an hour or two using the drip method. This will ensure that your animals survive better.
http://saltaquarium.about.com/library/weekly/aa111802.htm

Also I’d read all the articles at the top of this page to get yourself more familiar with SW.
http://www.aquariumadvice.com/showfaq.php?fldAuto=2

If you have any other questions don’t hesitate to ask as there are tons of helpful people with years of experience that can help point you in the right direction.

And please don’t take anymore advise from your lfs without consulting another source, they sound totally clueless and are just trying to make a buck

 

[dskidmore]

If you haven’t invested in a RO\DI unit yet I’d recommend it highly as you will have much better success with your SW fish and because your tap is likely contaminated with harmful chemicals (not just chlorine)

I've gotten in hot water on a diffrent board for saying this, but for an aquarium under 40 gallons, it is less expensive to buy your water from Wal-mart than to make it yourself. The wal-mart water machine near me tests out around 7 TDS, and is only 33 cents per gallon. RO/DI is also useful for your family drinking and cooking needs, so if you can afford it go for it, but I wouldn't get one just for a 29 gallon tank. Keep the replacement filter cost in mind when shopping for your filter. If you're planning on using it for your family needs, definately go for the more expensive model that comes with a pressure tank and faucet.

 

[tecwzrd]

for an aquarium under 40 gallons, it is less expensive to buy your water from Wal-mart than to make it yourself.

True since he only needs to change out about 6 gal a month. I use mine for drinking water also though

 

[dskidmore]

for an aquarium under 40 gallons, it is less expensive to buy your water from Wal-mart than to make it yourself.

True since he only needs to change out about 6 gal a month. I use mine for drinking water also though

My folks had one at thier last house. I miss it, but I'm not ready to invest myself yet. I don't have the cash to start up a saltwater tank right now.

 

[TheChad]

Maybe I missed it in the pic, but what are you using for filtration? I also can't see a heater in there but see the thermometer. Also, ditch the bubblewall and get a powerhead.

Peace_

What exactly does a power head do? I assume it just creates more suction than the bubbles threw the UGF tubes, causing more water to be pulled down threw the rocks into the UGF?


Would you need 2, one on each tube, or just 1 one?

I assume the Power head doesn't do any filtering, just creates more water movement?

Thanks,

-TheChad