I have been using the Nano Space 2 from OF (Ocean Free) for about two weeks now and it is time for me to share my thoughts on this nano tank.
I must say that I really like the simplicity and overall look of the nano tank. With the built-in filter, there is no need for a filter to take up extra space within the tank. The pump is really quiet and the strength of the flow is adjustable. A plus point is that this tank consumes very little power and water change is a breeze with a siphon.
Below is the LED lights in different modes.
I am not sure if you can see the ripple effect on the wall. It was mentioned on the box so I guess that is one of the selling point of this tank too.
Unfortunately, the tank do have a few flaws too.
First of all, I realized that during feeding times, most of the food tend to get sucked into the filter before the guppies could even finish their meal.
I have raised these guppies since the day they were born thus I am still feeding them with the leftover fry food in powder form. To combat this problem, I have to switch off the filter during feeding time which is not much of an issue to me. I suppose the problem will be solved once I switch them over to adult food. I have experimented feeding fry food and pellets for tropical fish but both were sucked in except for the goldfish's sinking pellets.
Next, I found that the plastic cover does not fit very well on the top of the tank. Again, this is not much of an issue as long as it can keep the fish in and the dust out.
Thirdly, the IOS filter system is the main reason why I bought this tank but it did not function the way I expected it to.
If you study the diagram below, the one on the left is what I expected the direction of the water flow to be like: water enters from the 3rd chamber and goes through chamber 3 and 2 before exiting from chamber 1.
However, as demonstrated by the diagram on the right, the two filter cartridge (white rectangle) does not sit all the way down at the bottom, thus, there is a "tunnel" below. Furthermore, the presence of the small hole at the bottom of the divider between chamber 1 and 2 creates a shortcut for the debris (white particles) to go from the third chamber straight to the first. The pump would then suck up all the debris and return them all to the front of the tank.
Fortunately, I found a solution (diagram above) that worked for me which is to lay filter wool (grey rectangle) above and below the filter cartridge to trap all the debris before they can make their way to the first chamber.
I understand the small hole is for the prevention of low water levels (in case water levels in chamber 3 and 2 is too low to overflow to chamber 1) therefore water still can flow from chamber 3 to chamber 1 via the "tunnel". So what I can do is to block the hole with filter wool therefore water can still flow through but debris will be trapped behind. However, the filter wool have to be changed frequently in case it gets clogged up.
Confused yet? I hope the diagram below can help you.
Despite all the flaws, I am still quite happy with the tank because the flaws I mentioned above can be easily fixed in one way or another so there is really no big issue.
The range of nano tanks on display at Qianhu Fish Farm's retail outlet
 for about two weeks now and it is time for me to share my thoughts on this nano...){kind=link}