Aquaclear seem to be the HOB filter of choice in this forum. I just started up a 10 gallon and put one on there. So I've only been using one for a month now. I have used biowheel filters since I was about 20. I can give you a breakdown of each.
Acuaclear cons
- The filter was extremely noisy. As the tank is on my night stand, this isn't a good problem to have. After doing some searching, I was by far not the only one to have this issue. Most say to pack the impeller and shaft with petroleum jelly to fix, but you will have to keep cleaning it out, and re-greasing. I ended up just putting a lot of grease on the shaft, and I experimented with teflon tape on the magnet. This helped with the noise, but didn't cure the issue. As I was lying in bed about a week later, the filter sounded like the impeller was hitting something solid and hitting it hard. This lasted for about a minute and then the filter began to run dead silent and has been that way ever since. (I know, weird right?)
-I set my filter up with pre-filter sponges and from bottom to top Eheim substrat, sponge, purigen. It's difficult to get the media basket out of the filter, because I didn't put the substrat in a bag. I am trying to emulate what makes Eheim filters so good, which is zero bypass. The filter does let some water bypass the filter media basket thus negating what I just tried to accomplish.
Aquaclear pros
-This filter is HIGHLY customizable.
-The flow is adjustable.
-The design is simple. (Because of this, it should be robust)
-No filter pads to buy
-Easy to clean
Biowheel cons
-Have to replace filter pads (although, I get mine to last at least 2 months...for anther thread)
-Moderately difficult to clean. What I mean by that is that it can be a pain to clean out the spray bars (which isn't very often). Also, you need to detach the spray bars to get to the impeller area.
-It has a rectangular intake. This may not be a big deal to most, but I like using pre-filters. There is no way for me to adapt to these filters cleanly.
- Zero flow adjustment. Plug it in, and let it go. I like to buy over sized filters, and turn them down a little. You cannot do that with these filters.
Biowheel pros
-Robust. I have had these filters for a long, long time and they just work. The Aquaclear is new to me, so I cannot say one way or the other for those.
-They keep your water clear. My fish have always looked like they were floating in my tank. I get the same results that others claim with purigen. I just started using purigen, and I am fighting a tanins issue right now, so I cannot really make that comparison at the moment.
-Somewhat customizable. There is an area to put different chemical filters in. I just fill mine with filter floss and change it out every 6 months or so.
-Usually quiet. I have sand and snails get in there (no pre-filter) from time to time. The best way to take care of the issue is to use a turkey baster and blow the impeller out while it's running.
Both are great filters. You can't really go wrong. Its all in what you want.
Best of luck!
