Running dual HOB filters, ideas for placement?

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Aquarium Advice Freak
Apr 18, 2007
Houston, TX
So, I am currently running an AC30 and an AC50 filter on my 55g tank, I will be building the plexi-glass lid to keep the fish from jumping out. I am in the process of trying to decide something, I currently have the filters hanging on the back of the tank, what about hanging them off the sides? Would it cause any problems, or not filter as well? I am planning to invest in a nice canister filter, just dont have the funds, or the research done yet. I am wanting to try to more evenly distribute the return stream, instead of pounding one spot in the tank. Also, what can I use to help slow down the flow from the return? The AC50 pounds the fish at the bottom of my tank...Can I use some of the scraps of plexi to make a deflector, what would yall recomend? I am trying to keep the stress down on the fish, and make it a more friendly tank for everyone...

Thanks in advance,

You can place them anywhere you would like and they will still function. I personally would keep them on the back. I am going to go against the common trend I see so often mentioned and say keep the HOB, no need for a cannister. We so often forget that some things function more than adequate for our needs but convience ourselves that "better" choices exist. The maintenance on the HOB doesn't get any easier or quicker. Also I will make the arguement that a HOB with proper selection of materials will have more than enough surface area for colonization of bacteria. I would just put more water in your tank. I use 4 AC in various tanks and none hit the bottom with the flow unless the water is too low. What fish are you keeping?
My 55 is filled to the bottom edge of the black trim at the top, and the AC50 moved the pleco's cucumber this morning when I dropped it in a little to far over. I dont mind the HOB's, and am not looking for easier, mearly to replace one of the HOB's. I am looking to setup a saltwater tank, and will need a filter for it. I will deffinately keep an HOB on the tank to help with the dissolved oxygen levels in the tank, but am looking for something to place the return a little lower in, and possibly filter more near the bottom where some of my fish hang out.

We currently have 5 black mollies (2 regular, 1 sailfin, and 2 lyretails), 4 guppies, 3 dojo loachs, 3 khuli loachs, 2 pleco's, 5 platy's (4 mickey mouse, 1 silver with red tail), 2 glass cats, 1 baby black mollie, 1 baby guppie, 2 black skirt tetra's, and 2 bleeding heart tetra's. I think that is our complete list, it sounds right. I know the filters work great, the water is clear as ozarka water, and the perameters are all good. Not sure of exact numbers, will test tonite.
You can reduce AC flow by moving the suction tube to the side as the arrow indicates. Some people have used plastic deflectors to move the water farther along the surface. Add a second extension tube to the AC to draw from a lower point in the tank.
ACs are very versatile, and you can add a second sponge to increase biosurface, and if you really want to reduce flow, you can put a smaller impeller in, as all the ACs other than the 110, use the same motor. The flow rates are determined by the impeller and size of the suction tube.
I dont want to reduce the flow of the filters, as I like the extra filter capacity. I have 2 AC's, one with an extension and 1 without, This way there is multi-level filtering. I think I may use some spare acrylic from the lid to use a deflector...

Thank you for the reply
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