How Much Water Flow For Fish in the USA


We generally recommend that on average, you turn over your aquarium volume four times per hour. This means that if you have a 30 gallon tank, you need a pump and filter with flow rates of around 120 gph.

How much flow should a freshwater aquarium have?

Generally, an ideal flow rate is four times the size of your tank. For example, if you have a 30-gallon tank, the recommended water flow for adequate filtration would be 120 gallons per hour (GPH). Presumably and hypothetically, the entire volume of the tank would “turn over” four times in one hour.

Do fish like flowing water?

While the actual swimming area remains the same, increasing water movement provides physical and engaging activity for fish. By swimming against or through moving water, fish receive physical activity necessary for proper growth and muscle development.

Is too much water flow bad for fish?

Defining “too much” water flow is very subjective. It all depends on your particular aquarium, the type of fish, or the plants you have. But if the fish are always struggling to stay in one place, the flow would be too much. Strong flow in a planted aquarium can push the plants so much that they lean over.

How do I calculate flow rate in my aquarium?

For example, consider your pump is able to fill the gallon container within 15 seconds. Divide the timed rate by 60 to find the gallon per minute rate: 60 divided by 15 equals 4. Multiply the gallon per minute rate by 60 to find the gph rate: 4 times 60 equals 240 gph.

Can you over filter a fish tank?

You can’t really over-filter an aquarium, but it’s fairly easy to under-filter one. This rating system works well for the most part, however, heavily populated aquariums, or those with large predatory fish or fish that generate large amounts of waste should be fitted with oversized or multiple filters.

How much flow do I need?

This is a loaded question, that really comes down to preference and the number of individuals that are in the home. The average household needs 100 to 120 gallons per person per day, and a flow rate of about 6 to 12 gallons per minute.

How do I know if my fish tank has too much oxygen?

The signs of too much oxygen in a fish tank are bubbles escaping the surface and increased dissolved oxygen levels. Fish will also show abnormal swimming behavior, open mouth breathing, excessive appetite, or lethargy. If left unchecked for too long, it can be fatal to the fishes’ health.

How do I increase oxygen in my fish tank?

The best way to increase oxygen is to increase the surface area of the aquarium. Increase Surface agitation or water movement on the surface. This allows more oxygen to dissolve and more carbon dioxide to escape. You can also add a source of fresh oxygen by installing an air pump.

How do you know if your aquarium is getting enough oxygen?

The most telling sign that your fish need more oxygen is if you see them gasping at the surface — they will also tend to hang out back by the filter output. This area of your tank tends to possess the highest oxygen concentration as it is near the most disturbed surface.

Can a filter be too strong for a fish?

You should check to see if your betta is swimming with ease. When the current in your tank is too strong, your betta may look like he’s struggling to swim. It almost looks like he’s getting blown around in the wind.

Should the filter be fully submerged?

Internal filters must be completely submerged in the water to work correctly. Air is pumped into the filter and moves through it. Then it is dispersed on the water surface. The air bubbles create much-needed movement in the water that allows it to filter the liquid throughout the entire tank.

How many GPH does a 120 gallon tank need?

I’ve been into aquariums for a while and I know that GPH should be at least 10x the gallons in the tank, however, I just got a 120 gallon tank that came with two Fluval canister filters. 335 is the total GPH.

How many GPH does a 29 gallon tank need?

A good rule of thumb to follow is that a pump should have a flow rate of 5 GPH (gallons per hour) for every gallon of water in the aquarium. For example, if you have a 29-gallon aquarium you will need a pump with a flow rate of at least 145 GPH to effectively turnover the tank.

How high should filter be in fish tank?

When its a canister filter you have, the output should sit about 1.5 to 2 inches below the water surface (fully submerged) pointed to the surface for better agitation. If you place the canister filter above the water level, there will be a lot of splashes, which apart from going everywhere, they make quite the noise.

Can I run 2 filters in my fish tank?

Don’t Multiple Filters “Compete” on the Fish Tank? It is true that if you use more than one filter on your fish tank, neither of those filters will perform as efficiently as it would if it were the only filter on the aquarium. This is expected, but is not a problem.

How long fish live in tap water?

Ordinary tap water is fine for filling up the aquarium as long as you let it sit for several days before adding fish (the chlorine in the tap water will kill the fish).

Why are my fish swimming at bottom of tank?

Sitting on the Bottom: If your fish is spending lots of time at the bottom of the tank, it may be normal behavior. If you think this is the case, you should quarantine the fish. A common disease that would cause this behavior is a swim bladder infection, which is a result of a poor diet or water quality.

By kevin

Recent Posts