How Do You Measure Water Flow?

[Tag2008]

Hi Guys..

I Have an external fluval filter and a built in filter im my 180 Litre tank..I dont recal my externals model but its for a 200 Litre tank if i recall .

When its running you dont realy see any water "flow or current" realy, the plants sway a little but it doesnt seem torrentual..

I see some fish kind of playing directly in the outflow of my filters and they even seem to be enjoying it and others dont seem to go near it.

Ive seen a few posts that mention defusers to cut down the flow etc and wonder how you know whats too much?

What probllems would too much flow give you and should i have defusers?

Regards as ever
Tag

 

[Axleuk]

I think it depends on the size of the fish and whether not they show any signs of discomfort. The smaller fish should be smart enough to stay away and having a big tank will give them plenty of area to swim in. If the other fish seem to enjoy it, then i dont think you have much of a problem.

You mention that the plants seem to sway a little which is fine, but if you start seeing bits of plants floating around then it might be a little too high in which case a difusser is an option, otherwise it sounds your setup is fine.

 

[Mauricia]

A lot of the talk about blocking some of the current is for fish like bettas that have long fins and are from fairly stagnant waters, and can't handle much, if any, current. Also if you have a fry tank you wouldn't want the fry getting blown around.

 

[rdd1952]

Most likely, it is still barely strong enough for the 180. Most manufacturers say their filters are for such and such size tank when in actuality, they don't really process enough water to truely handle the larger tank. For a 180L tank, you need a filter that is rated at 900L per hour. As mentioned, you shouldn't need to block any of the flow.

 

[aaronnorth]

I presume you have the 205 with a flow of approximatley 600lp/h (3x turnover)

I try to aim for 10x turnover mminimum in any tank i have.

 

[Tag2008]

Hi Guys,
Thanks for the replys,
I looked at the filter and its the 305 model I have and it says 1000 LPH for aquariums up to 300 litres

 

[OldMan47]

Your 305 should be plenty for the average tank your size. If you have a tendency to overstock, which some people do, it would be good to leave the other filter in there but otherwise it shouldn't be needed. As others have already said, if it doesn't blow your fish around in the tank, most of the fish will probably enjoy the flow. The first step if you do have too much flow for your fish is to try pointing the return hose back toward the side of the tank. That will usually cut the flow impact on the fish more than enough. I am running a summer pond (tub) with a filter that sort of makes it look like a whirlpool and the fish seem to be fine with it. They are happy and their growth is noticeably good. If flow were proble, I'm sure they would be trying to hide from the flow but they ignore it and just swim around.

 

[Tag2008]

Your 305 should be plenty for the average tank your size. If you have a tendency to overstock, which some people do, it would be good to leave the other filter in there but otherwise it shouldn't be needed. As others have already said, if it doesn't blow your fish around in the tank, most of the fish will probably enjoy the flow. The first step if you do have too much flow for your fish is to try pointing the return hose back toward the side of the tank. That will usually cut the flow impact on the fish more than enough. I am running a summer pond (tub) with a filter that sort of makes it look like a whirlpool and the fish seem to be fine with it. They are happy and their growth is noticeably good. If flow were proble, I'm sure they would be trying to hide from the flow but they ignore it and just swim around.

Thank you,

I have 5 american flags, 1 dwarf flag and 2 keyholes in this tank and have 2 severums on route from tri mar... that will be this tank complete I think except the american flags will get moved out at some point. Im not one for keeping tooooo many fish in 1 tank, If i had my way id just have a nice pair of something

If i were to disable the intenal filter would this cause a spike in my nirtogen cycle in anyway or would my bacteria in the external cope with it all?

Regards as ever
Tag

 

[OldMan47]

Assuming that the external has been runnuing on the tank for a month or more, I would be surprised if you noticed any spike at all. The question in my mind is why shut it off. It's not hurting anything, and if you have trouble with the 305, it would make a good backup to avoid your cycle failing on the tank.

 

[Tag2008]

Thanks Oldman,
I will leave it running,
It was just how you worded your last reply saying I didnt need it i thought perhaps i should turn it off..Just me being Dumb.. soz
Thanks again