Hello,

I have an 80 gallon aquarium that is currently being filtered by a fluval canister filter. I also have 2 large goldfish that are producing far too much waste to keep the aquarium attractive. After several disgusting bursts of worms and a newly established population of gammarus shrimp, I have decided to add an undergravel filter to help out. I've never used an undergravel filter and have a few questions that I thought someone on this page might be able to help me with. Which is better powerheads or airpumps, and why? Since undergravel filters are a method of biological filtration should I stop using biological filtration in the canister filter and replace it with a different mechanical or chemical type?

Thanks,
Amanda :blink:

I'm not a fan of undergravel filters but to each his own. Using bubbles to run it will give a slow flow, providing a reasonable bed for good bacteria. Powerheads will give you much more mechanical filtration (be sure to gravel vacuum that out of the gravel often) and more water flow and aeration (a more "active" water column). Since you already have another filter, I don't think you need the powerheads but it's up to you. Perhaps just a better overall filter would work for you. A couple of Emperor 400 filters would probably do a better job in my opinion than the one canister filter and a UGF or maybe you could get one Emperor and continue to use the canister. An 80 gallon should be able to handle even two large goldfish with the right filter. I would not discontinue the biological filtration in the Fluval, at least not right away as the bacteria have to move to their new location. What I would do is perhaps reduce the area for the biological filtration in the Fluval but not delete it and only after a few months of running the new filter so it's established. The tank could probably use more mechanical filtration that is cleaned often. Chemical filtration is good for removing smells and organic stuff (foam, etc.) from an overloaded tank. Good luck!

Is the Emperor filter a brand? I currently have a Fluval 404, heard anything about it? I go away to college and have had to leave my tank for my parents to take care of, so I would like to have a system that isn't too much of a burden on them. They have been doing a 1/4 water change for the last couple months but it just doesn't seem to be doing the trick. I thought they might be overfeeding, but I've seen how much the two fish get fed and I'm positive that's not the problem. After the worm and shrimp population began to explode I took I gradually took all the rocks out, which helped, but now I have a bare and unatractive tank. One of my "Goldfish" is about six inches and the other is about eight inches, could they be too big for the tank. Overall I just want a filter system that is fairly low maintenance and very efficient. Sorry about my spelling, it has been a long day.

-Amanda

The Emperor filter is made by Marineland which is the company. I've never had Fluval filters myself so cannot comment on them. The Emperor is a hang-on-tank filter with catridges that are easy to change. I have a canister filter on one tank (Magnum 350, also by Marineland) that's a real pain to take apart and clean plus sometimes it leaks. So, I like hang-on-tank filters. You don't have too much fish mass for 80 gallons I don't think. I recommend them doing more like 30% water changes weekly. That may help. There is no reason not to put some gravel back in. You can kill what's in it either by letting it fully dry for a while (which may not kill everything) or soaking it in bleach for a few days with stirring and then soaking it in fresh water with dechlorinator for a few days in buckets until there's no bleach smell left. That will kill everything. The worms and shrimp would seem to indicate an excess of food was present to feed them, perhaps some food was getting in the gravel where larger goldfish can't vacuum it up.

Thanks for the suggestions!
Amanda