Tropical Fish Forum

Tropical Fish Keeping Help and Advice => Fishtank Filtration and Cycling => Topic started by: Littlefish on January 23, 2019, 11:04:26 AM

Title: Filter placement in tank
Post by: Littlefish on January 23, 2019, 11:04:26 AM
This may seem like a very simple question, and considering the amount of tanks I have, this should have crossed my mind a long time ago, but.......

When setting up an external filter, should the intake be on the same side as the spray bar/output, or should it be on the other side of the tank?

Also, does the placement have any influence on the circulation? and how much surface movement is required for gas exchange to take place?

I feel like a bit of a doofus asking these questions now, but better late than never.  ;)
Title: Re: Filter placement in tank
Post by: Sue on January 23, 2019, 11:51:54 AM
It is usual to have the tube that takes water out on the opposite side from the tube that returns the water. The argument is that if they are both on the same side a good proportion of the returning water gets pulled straight into the out take tube.
Title: Re: Filter placement in tank
Post by: Littlefish on January 23, 2019, 09:29:17 PM
Thanks @Sue
I've normally set them up at opposite ends, but some of my tanks can be viewed from one side as well as the front. This is the case with my tiger barb tank, but the spray bar is clear, so I've put that at the end that the fish can be viewed from, and it's not too much of a distraction.
Title: Re: Filter placement in tank
Post by: jaypeecee on January 24, 2019, 01:50:12 PM
Also, does the placement have any influence on the circulation? and how much surface movement is required for gas exchange to take place?

Hi Littlefish,

The placement of the inlet and outlet pipes will affect the circulation and I agree with Sue on this. Regarding circulation, I have come to the conclusion that some external filters are inferior to internal filters in this respect. So, I supplement my external filter with an internal circulation unit.

As regards how much surface movement is required to ensure adequate gas exchange, this is important particularly when injecting CO2 for the live plants. I measure dissolved oxygen using the JBL O2 Test Kit (the new version) and dissolved CO2 using a drop checker plus the JBL CO2 Direct Test Kit. Both these gases need to be measured at different times of day.

JPC
Title: Re: Filter placement in tank
Post by: Matt on January 24, 2019, 09:29:19 PM
I agree with all of this though would add that if not using a spray bar, and say using Lilly pipes instead as I do. Placement is best at the same side of the tank with the outlet directing flow away from the inlet to generate a circular motion of w a term in the aquarium avoid dead spots.