Do I need to change my goldfish water 50% every week?

Question

His tank just cycled. All readings, ammonia, nitrite, and nitrates are at zero for 10 days. His last water change was a week ago. There are three large plants and 1 1/2" goldfish in a 16 gallon Biorb aquarium. There is no cloudiness in the water.

If there's no ammonia or cloudiness should I change the water? Also, if you think I should, how much of a water change should it be? 50%? 25%? I know that with goldfish it is routinely weekly at 50%.

For the future, can I rely on chemical readings, or just routinely change water?

There's a little algae in the tank. Not bad but a sign it's cycled.

Answer 1

Personally I like a 25% water change as a typical water change, but of course some tanks require more to stay clean. As your goldfish grows, your tank will require larger water changes up until the point the goldfish outgrows the 16 gallon tank.

I only check things like ammonia, nitrites etc when I think there is something wrong. A weekly water change will handle small problems that occur and for major problems you will have an indication from the fishes behavior.

MM

Answer 2

Probably a lot of reasons. 1. You're overstocked. 2. You're not changing the water correctly and you're changing too much. 3. Not enough filtration and that's why you're having to change so much water. 4. Adding too many fish at one to keep replacing the ones that die. I'm guessing you have the cheap common/comet goldfish since you are replacing them so often. Do you know that just one of those fish needs a minimum of 75 gallons with a filter double the size? And for every other goldfish you need to add on another 50 gallons. This is probably your main problem, these fish are very messy and will grow to be over a foot long when they're adults. If you do have fancy goldfish by chance, they still are very big and messy so you need at least 20 gallons per fish still with a double rated filter. Next, you should never change more than 50% of the water. Have a liquid test kit so you can test the water and then you will know how often to change it, but 100% water changes are very bad. The fish should stay in the tank while you clean it. NEVER take out the fish. Use a siphon to get out the old water, then put the new water in and make sure you use water conditioner first. Ammonia and nitrites should always be at 0, nitrates should be as close to 0 as possible. Never add more than 1-2 fish every couple weeks. Since goldfish are so messy your tank needs time to adjust to the new bioload otherwise you will have an ammonia spike. But by the sound of it, you don't need to be adding any more fish, if anything you should get rid of some or all of them if you don't have the basic requirements. Doing about 30% water changes every week should be enough, but if you have too many goldfish in a small tank with a bad (or no) filter your water will get dirty very quickly and this will be a problem. Get things under control before replacing any fish if they die. Goldfish are not easy fish to care for, they need large tanks, they produce a lot of waste, and they live a long time (about 20 years). They're not for beginners. You may want to consider a small tropical community instead.

Answer 3

Assuming you have a filter, you should never do more than a 25% water change. Doing more than that could hurt the fish (e.g., drastic change in PH, reestablishment of beneficial bacteria).

If it's 16 gallons you could probably just do a 25% water change every month or two when you gravel vac. If you don't have a gravel vac go to your local pet store and buy one. It uses water displacement to vacuum the solid wastes that have settled in the gravel.

Answer 4

15 to 25 percent weekly is fine. You need to do water changes to lower nitrates and keep the other impurities from building up.

Answer 5

do water changes every week 10% to 20% and check your water with the chemicals once a month to big of a water change will unicycle your tank

Answer 6

50% is not bad. But no more because there are, believe it or not, good bacterias present in the water that help keep the tank clean, specifically in gravel where the "poo" floats to. This bacteria helps break down the excrement(?). If what you are doing is working, then keep it up I say. If it ain't broke, don't fix it.

Answer 7

I have a goldfish an I change the water everyweek. So yes change your goldfish water every week

Good Luck with that!

Answer 8

I say get a algea eater and a cory, and just clean it once a month. Goldfish are messy though so maybe twice.

Answer 9

25% once a week is good. If you find your ammonia or nitrates are going a little higher, go to 30%

Answer 10

yes