Bests & Worsts Reviews from Amazon

PROS: 1) Works great in 3 gallon tank, keeps water filtered clear. Have no doubt that this filter could easily handle upto 10 gallons. 2) Extremely quiet <--don't underestimate this. This is a MAJOR plus. Very little vibration if you attach the included black knob (see notes below). 3) Has adjustable flow control knob on top (might have to make a slight mod, see notes below.) 4) Does not require external pump (pump comes attached to unit) so you don't have to snake tubing and risk backflow if power goes out. Also saves you from having to buy a check valve. If power goes out, the water will simply rest in sump. 5) Comes with prefilter <--an absolute MUST to protect fish from getting sucked into the intake!!! CONS: 1) Instructions that came with the unit are extremely vague and frankly not helpful. (see my attached photos to clear up almost all of the questions that people are asking about this unit including where to put that black knob). 2) The 2 sponges it came with seem to be low quality (see notes below). 3) Even with the adjustable flow control on the top of the unit set to max, the current was too strong for my Betta in a 3 gallon setup. Had to do a simple MacGuyver mod (see notes below). BOTTOM LINE: BUY THIS if for 3-10 gallon tank. I've looked at pretty much all the filters available for small Betta tank and this is the one to get if you are looking for a quality filter with easy install that won't break the bank and is safe for your fish (If you put on the included prefilter and set the suction/flow to low). NOTES: First of all, please click on the pictures I uploaded as I put in annotations to answer most of the user questions that keep coming up. I HIGHLY suggest not using the low quality sponges and instead use Aquaclear Biomax 20 Aquaclear 20-Gallon Biomaxand Aquaclear sponges.AquaClear 20 Foam. The biomax adds an extremely high amount of surface area for "good" bacteria to culture on and grow. The Aquaclear sponge will also allow beneficial bacteria to grow on it but also traps larger debris from going back into the tank. Now please note the following are SUPER IMPORTANT--> A) You should ALTERNATE cleaning the biomax and the sponge monthly WITH THE SAME TANK WATER or else you will kill the "good" bacteria that eventually grown on them and might cause the filter to recycle! (google "aquarium nitrogen cycle"). B) Example: During your water change, SAVE the water you take out and put it in a small container. Rinse out BOTH the biomax and the aquaclear filter for like 5 seconds each in the saved water you took out by gently and loosely just rocking them back in forth in that water just to break up and take off any large debris. Then put one of them back in the filter (your choice, either the biomax or the sponge but remember which one or write yourself a note). The one you didn't put back can get a more thorough rinse out in the aquarium water you took out and when you are done put it back in the filter. Next month do the same thing but ALTERNATE which one gets the thorough cleaning in the same aquarium water you took out. C) Placement does matter: Sponge should be on BOTTOM and the biomax should be on TOP. I also highly suggest, as another reviewer did, you goto youtube and look up "asiandude666 How To: Setup Azoo Palm Filter" as he walks you through putting in the Aquaclear products. (OPTIONAL) The flow was too high for my Betta, Sushi, even with the flow control set to make the minimum amount of water come out, so I just used the black foam that came with the unit to block some of the flow. The black foam fits exactly to the width of the opening of the water out spout. MAKE SURE you point the foam DOWN into the water or else it will force the water to flow OUT of your tank!!! You can cut off the excess black foam so that it just barely goes past your water fill line (makes it almost unnoticeable / not an eye sore). Don't just stuff the black foam in and walk away. I just barely placed it in the opening and used the filter's own lid to hold it in place. If you stuff it too far in, you will block the water coming out risking it to backup the water, cause the unit to overfill and leak water onto the floor. Always check to make sure where the water level is on the inside chamber so you don't risk leaks. Also, you should set the water flow to its lowest setting (it's the knob on the TOP of the unit that turns). By default, it's set fully open (maximum suction/flow) so you will have to turn it down (for me I turned it all the way down). Again, see pics I uploaded to show explanation.