Eheim6666 Pro 4+ Canister Filter

Like many the name of the filter listed confused me but I took a gamble on the few people who specified it to be a mislabeled 350 and I'm more than happy since it's exactly that. I got it for $169 compared to the 250 on Amazon for $160.On to the actual filter, I'm using this to replace a SunSun 304b. This filter is compact at almost half the size. It's easy to carry, if you've owned the 304b you know lifting up the filter by the latches makes them pop out and it becomes annoying to move. Eheim actually put a plastic ledge the latch sits on so that when you grab it you're not holding the latch and can actually pick it up with ease.The 3 media trays have 2 medium/fine sponges and a Polish pad on the bottom tray, and completely filled with matrix on the top 2 trays. I don't use the extender bottom as I don't see the use for it currently. I ditched all the Eheim media it came with since it wasn't really that good or that much. I did reuse the plastic media and put it on the bottom of the blue sponge that's at the top of the filter. To help catch and retain more gunk before entering my bottom tray. The media trays hold almost as much as a Sunsun tray.The hoses were easy to put on and overall the set up of this filter is more streamlined and minimalist than the Sunsun. Every piece is specifically fitted together and inconsistencys are easy to spot and correct. I love the intake since it's easy to hide and replaced the grate with a mesh cover for my baby fish. I don't miss the surface skimmer my Sunsun had since the Eheim outlet is high enough to disturb the surface tension.Overall thinner in every way than my Sunsun while remarkably more powerful. The premium you pay with an Eheim is well worth it with this filter.

I have an aquarium pig, in other words african oscar, and you may know how these fish make the water dirty in a couple of days. I have two large hang on filters, one UV light filter, and eheim 2217. With these filters, I also changed my water every two weeks. But still my tank was always dirty with particles of dirt moving around in the water. I added this filter and I was amazed how this thing cleared up my tank in just a day! The water current is also very great which keeps the water circulated in my 55 gallon tank. Look how clear my water is even from the side of the aquarium which is 4 feet deep! Unbelievably clear water=happy fish!

I've been running this filter for about 6 months. The first filter I received had a broken clip Amazon quickly sent a replacement which had the same issue. Since the price was so good I decided to just purchase a replacement clip. This filter is extremely quiet and holds a lot of media and heck it's an Eheim so it should last a very long time. Not so for this filter, I was preparing to clean the unit but the red release button was stuck so I could not disconnect the adapter that the hoses were connected to. This filter also started making a "whining" noise. Eheim support told me the adapter was the issue and I would need to take apart the head unit to remove the bad adapter. Before I was able to do this though the filter stopped working completely I'm guessing it had something to do with the whining noise, I did check the impeller and it appeared fine. I finally get a chance to disassemble the head unit which was a huge mess. The only way I can see to get the adapter out is to break part of the head unit. Maybe I was unlucky and got a bad unit it happens. The biggest issue and disappointment has been Eheim's support. They told me the adapter would not be covered under warranty because it was considered normal wear and tear. I have a hard time blaming the issue on that when I've only been using it for six months. After the initial issue the filter stopped working and I've tried to contact Eheim's support several times over 2 weeks and they have not responded. Luckily I had a back up filter and I'll be looking at other brands. Very disappointed to spend as much as I did on this filter and have to replace it 6 months later. I probably could have tried to get replacement parts but after dealing with Eheim's support I didn't want to give them any more money than I already have.

4 stars for initial setup. Everything was in perfect working order when it arrived. Setup was easy. I received the 350 model as hoped for. But hopefully eheim reputable name stands up for the test in my 80 gal freshwater aquascape. Will update my review 90 days from now for solidified reviewEDIT***so far so good. Cleaning the filter is a breeze. The 350 model holds up pretty well in my 80gal, wish I got the biggest model but that's okay. This filter is great. If your thinking about buying it. Just do it. Great water flow, the extended feature actually works as eheim intended. Super pleased with this purchase. Do your homework before you buy. If this filter is in your top 3. Just get the eheim. Forget fluval or aquatop. The flow is great and the containers are very customizable.

2 months in and it’s running beautifully. Very quite. Open after 1 month to swap out media and filter pads, No issues

I had to return this because after less then a month pump button broke and no water would intake. Yes I left the flow lever open.If it had a better pump design it would have been a really good unit.PROSAmazing intake suction and output flow.Clips holding head to body really sturdy and well constructed.body of it well constructed.quick release easy to usesquite operationCONSNo individual flow control for intake and output.The switch/lever to adjust flow control is easy to break ofPump button is a horrible design

This is the best filter I’ve ever owned and I’ve owned a lot of filters over the years, does a great job of filtering my 55 gallon aquarium with African Cichlids, easy setup, easy maintenance and super quiet