I think I understand filter pump max GPH however...

Only my 4th day with this fish thing but I have another newbie question.

It's my understanding that GPH should be 5 times the number of gallons in your tank. I have a 5 gallon tank so based on what I've read it should exchange 25GPH.

However this is where I need some help understanding. My new 5 gallon aquarium kit includes filter and pump. However, in the literature nor on the pump itself can I find its GPH rating (I expect I will need to replace the pump sooner than later since it is part of a kit). While I don't consider that a big deal while I'm doing my fishless cycling (I have the pump set as high as it will go) it MIGHT be once I add my male betta fish which prefer calm waters so they don't get buffeted by the outtake. I plan to run the pump at its lowest setting (at least initially) once I have introduced my betta and have also purchased a pre-filter sponge to put on the outflow to further reduce possible buffeting.

So far so good. BUT I'm concerned about not really having all the facts I [think] I need. I have also discovered that buying a pump with a low GPH (40GPH seems about as low as I can find) can be difficult. There don't seem to be a lot of options.

FINALLY I am at my question. While manufactures love trumpeting their MAXIMUM GPH I'm also concerned about the MINIMUM. Question: Is there any sort of standard ratio between maximum and minimum based on settings. For example if I buy a 400 max GPH pump and I turn it down all the way will the minimum be 50% of the maximum (200GPH), will 25% of the maximum be (100GPH). Is it linear or is it just a shoot, trial and error, hit and miss?

I'm would be nice to know enough to get the highest Maximum GPH pump that also meets my current Minimum requirements (future needs may change). Certainly I would expect a max 40GPH pump to be adjustable to the 25GPH I require but how about a max 80GPH?

Any thoughts? Is this really an issue or am I making it more difficult than it needs to be? Thanks!

 

I wouldn't get too bogged down with GPH figures. If you have a filter that comes with a tank it should be more than adequate for at least medium stocking levels. A Betta in a 5G shouldn't be too much of a load.
A faster pump doesn't mean better filtration, although more water goes through the filter the residence time ( the time the water spends close to the bacteria covered media) is less so the filter becomes less effective. There is an optimum flow for any filter system and an all in one kit system is probably well set up for it.
After the tank is cycled I would try turning the flow down, add the betta and monitor the water chemistry. If the water parameters remain good then the filter is more than adequate.

 

I wouldn't get too bogged down with GPH figures. If you have a filter that comes with a tank it should be more than adequate for at least medium stocking levels. A Betta in a 5G shouldn't be too much of a load.
A faster pump doesn't mean better filtration, although more water goes through the filter the residence time ( the time the water spends close to the bacteria covered media) is less so the filter becomes less effective. There is an optimum flow for any filter system and an all in one kit system is probably well set up for it.
After the tank is cycled I would try turning the flow down, add the betta and monitor the water chemistry. If the water parameters remain good then the filter is more than adequate.

Thanks! Your explanation about load, pump speed and application of using s pump is very helpful. - I plan to reduce the flow once I've added the betta and as you point out I expect that the filter/pump that were included are appropriate for that kit.

Where I started getting confused (and started wondering out minimum GPH compared to maximum GPH was when I began evaluating pumps with the thought of puchasing a backup in case the one I have fails. I found the selection of lower maximum GPH (such as 40) pupmps is limited. An 1,000GPH would not be ideal. That is why I was wondering if for instance if I got an 80GPH (because i liked it because of the brand, dimensions, customer satisfaction, etc.) if the minimum were published I would know if at the lowest setting the current was too strong for my betta.

I also appreciate your comment about greater (faster) flow may not be as effective because the speed would mean it was spending less time in contact with the media/bacteria perhaps being less effective than if might at a more optimum setting. Good stuff for me to know.

I'm not sure if minimum GPH is really an issue in most case but I'm a detail and data kinda guy and it seemed to me that information would be helpful to me.

 

GPH figures can be misleading, they don't take account of the filter type ( filters with denser media slow the water down more ) or the head ( higher heads slow down water more ) . The figures stated only tell you the flow rate at minimum head and with no resistance from the filter.
When buying filters / pumps the packaging usually gives a recommended tank size which is more useful than the GPH figures.

 

GPH figures can be misleading, they don't take account of the filter type ( filters with denser media slow the water down more ) or the head ( higher heads slow down water more ) . The figures stated only tell you the flow rate at minimum head and with no resistance from the filter.
When buying filters / pumps the packaging usually gives a recommended tank size which is more useful than the GPH figures.

Thank you! I didn't know that. I usually buy online and had not even thought of looking for tank size although often times the packaging is not shown. May have to go to my friendly neighborhood fish store.

 

If your tank came with an adjustable flow on the filter, then just keep that and use it.

I agree with Heron.

There is no absolute rule for gph and tank size.

You can run a tank with only sponge filters driven by air pumps, and their flow is a lot less than a HOB style filter.

A betta fish does not require much filtration.

What filter do you have?

 

If your tank came with an adjustable flow on the filter, then just keep that and use it.

I agree with Heron.

There is no absolute rule for gph and tank size.

You can run a tank with only sponge filters driven by air pumps, and their flow is a lot less than a HOB style filter.

A betta fish does not require much filtration.

What filter do you have?

Thanks. While I agree that there is no absolute rule for gph and tank size, since I'm brand new I was hoping to get at least a range of min/max parameters.

Telling you exactly what filter I have is a problem. When I go to the kit sellers site using any part number provided in the User Guide supplied by the retailer it shows as either "Sold Out" or "Unavailable" so I have no idea what the pump or filter brand is, model number or what its specifications are. In fact in response to somebody else's question about purchasing a replacement for the filter/pump the retailer responded "it is not sold separately".

My solution: I pitched the provided cartridge carrier, small chemical filter and similarly small sponge filter with foam sponge filter I cut to fit that is roughly twice the volume of what I replaced. The provided pump seems adequate for fishless cycling where flow is of no consequence to the inhabitants.

That leaves me with the original filter hose and original pump (of unknown specifications) and my Jerry-rigged sponge filter. We'll see how well that works while I finish cycling and later introduce a betta.

The lesson I learned: While it may initially be more convenient for somebody new like me to buy a kit, in the long term it may not be such a great idea as far as building a knowledge base and being able to replace/upgrade components as needed in the future. For example, with this kit, even the glass cover provided, should I break it, is "Not Available". Live and learn I guess layful:

 

A general guideline is 4-6 times volume turnover per hour. But there’s a lot of variables and every situation is a little different.

Some of those complete kits can look very nice and may appear to be convenient but I do prefer to buy tanks, filters, pumps, lights, heaters etc separately so that I can customise everything to my liking. Generally all that a 5 gal needs is a small air driven sponge filter. There’s always that option if you continue to have issues with the built in one.

 

A general guideline is 4-6 times volume turnover per hour. But there’s a lot of variables and every situation is a little different.

Some of those complete kits can look very nice and may appear to be convenient but I do prefer to buy tanks, filters, pumps, lights, heaters etc separately so that I can customise everything to my liking. Generally all that a 5 gal needs is a small air driven sponge filter. There’s always that option if you continue to have issues with the built in one.

4-6 times volume turnover sounds about right (plus variables). I think the variables in my case are 1) I don't know what my pump is rated for, 2) Whatever pump I use will need to be adjust, trial-and-error so it doesn't stress my betta while at the same time 3) Giving me enough flow so that it does an adequate job of filtering well.

As a beginner I fell for the complete kit idea. But that was because I hadn't really researched enough. In my ignorance I had 3 criteria: 1) That the tank looked really cool, 2) That it fit the space I had available and 3) That it was suitable for keeping a betta. Little did I know I should have considered so much more but I'm learning and most of that knowledge comes from people like you that are helping me on this forum. Thanks!