External Filter Maintenance

[alanthomaswatson]

Folks

I'm setting up a new fish tank and am installing it within an old fireplace. (I have one in there already which has been successful but want to move to a larger tank).

The dimensions around the tank are pretty tight but I have enough space for maintenance, planting etc.

However, the only way I can do this is to have an external filter sited outside the fireplace with the pipe running through the wall. The plan is that when it comes to water changes I will utilise the pump and filter pipe that normally runs back to the tank to dispose of the old water. I was thinking of installing a valve and T in the return pipe so that I can do this by simply opening the valve and running the filter.

My basic question is whether this is possible. I was looking at a unit like the Fluval 205.

Apologies if this is a really simple or dumb question but help much appreciated.

 

[thedc5]

cant see why not

I do water changes using a power head so same principle, saves me bucketing tons of water around the house

Only problem you might have is the filter being the same height as the tank?? i think there supposed to be below arnt they? mine are always in cabinets so not tried them on the same level.

 

[alanthomaswatson]

cant see why not

I do water changes using a power head so same principle, saves me bucketing tons of water around the house

Only problem you might have is the filter being the same height as the tank?? i think there supposed to be below arnt they? mine are always in cabinets so not tried them on the same level.

Thanks for that. The fireplace is actually raised and the filter would be on the floor so that one should be sorted.

 

[waterdrop]

Yes, thedc5 is correct, you want to study the specs of the actual model filter you choose and be sure you can site it to achieve the correct height. Externals need to be not too low or high relative to the tank height. You also need to be aware that extra length of tubing significantly increases the work the pumphead must do because of surface friction and that if you're getting to the longer limits of what the pumphead can achieve, it will be more sensitive to the additional slow-down caused when the debris and algae hasn't been recently removed from the interior tubing walls. Other than that, extra functions done along the water return path, like a valve, should not be a problem.

~~waterdrop~~

 

[alanthomaswatson]

Thanks again. I can easily sort out the height of the filter as it'll be sat on the floor so I can raise it if need be.

As regards the pipe, any advice on how long is too long, or is this pump specific? Whilst it will be going through the wall, the pipe shouldn't be longer than about 4 feet.

Thanks again

 

[waterdrop]

Ideally one finds that buried in the user's manual for the specific filter. To me, given you will use most or all of the hose length they give you or even extend it, I would consider it to be an invitation for a little adventure to see if I could get through to tech support or even one of their engineers and get that warm feeling that comes when you feel you've had it answered even more definitively (but I tend to like arcane stuff like that.)

Another thing that might have a bearing is that one of the things we often discuss about filters is that there is a difference between finding the actual technical spec for "flow rate" (and then calculating what turnover rate that gives you) versus only noticing the "this filter is for XX Liters/Gallons of tank" message that the marketing people put on the box and elsewhere. Sometimes they are different things. At TFF our usual recommendation is that 5x may be a minimal starting place (but good aquarists are sometimes doing only 4x and planted tank enthusiasts usually are up at 10x if they are doing high-tech approach.)

The upshot of this is that one sometimes realizes that the "next size up" of external cannister might be better (if one can afford it.) Reality always delivers a lower flow rate than one thinks from reading specs. In your case you might have two reasons to go up a notch! The competition in the class of filter you are looking at, by the way, is between Fluval, Rena, Eheim and Tetratec/Marineland. They all have Pros and Cons.

~~waterdrop~~

 

[alanthomaswatson]

waterdrop

Sorry, when you reference calculating turnover rate, can I have an idiot's guide please?

Thanks