inTank Chamber One Media Basket for Fluval Flex 15 | Fluval Flex 57L

I purchased both the Chamber 1 and Chamber 2 baskets for the Fluval Flex 15gallon. The chamber 1 basket had to be modified in order to fit into chamber 1, and even then just barely. I had to file down the edges that were left uneven where the side and front/back pieces join. Still a VERY tight fit that bows out the Flex's black false wall. Water flows freely between the basket and the false wall at the topright side, completely bypassing the media basket. I had to glue in an acrylic piece to force the flow into the basket. The design of the Flex has a plastic piece sticking off the false wall, near the bottom, and this basket has a notch cut into it that slides over this protrusion. This makes adding almost anything into the basket damned near impossible, as it simply gets in the way of alowing the basket to slide into place. I had to cut that piece out of the tank. The little black "Water Direction piece" is completely useless. First it is so thin and brittle that it was broken in the box and had to be glued back together. Secondly, the notches in the "arms" are cut way too wide and it sits so loosly in the vent that it simply floats out and bounces around in the basket top. If it were designed in a way that that would have stayed where it was intended to be it would still make the stock Flex vent cover impossible to reinstall.The Chamber 2 basket is far less flawed, but still could use some revision. There are no sides on this "basket". This allows the Flex's flow path to still enter chamber 2 a little too low, bypassing flow to the top shelf of the chamber 2 basket. The lack of any sides to this basket (and how loose the 2nd shelf is in the basket) also makes the removable 2nd shelf want to fall out when either installing or removing it from the tank. Whatever you put on that shelf will try to fall out with the shelf.For the price of these baskets I was expecting a product that was not only designed far better, but one that had significantly better build quality. I have acrylic and tools on-hand, and will be modding these to work better in the Flex. This was my first purchase from this company, and it will be my last. These baskets should cost $15 to $20 each for the design and build quality received and are in no way worth anything even close to the $113 they are now.

The basket blocks the guard for the bottom grate so you have an opening for one of the grate slivers. Inevitably, shrimp easily swim through it and further through the bottom green holes into chamber 1. Now, I don’t have a problem with this as they can swim back. What I DO have a problem with is that the basket does not fit snugly into the chamber. There is a small gap between the basket and the left wall which I have had two shrimps get stuck in within four days of installation which has led to late nights trying to ease the shrimp out between the wall and the basket. I have a feeling one of these nights a shrimp will get stuck between basket and the wall and will die from stress. I have decided to remove the basket for now and just leave the bottom grate there for the shrimps own good.Basket idea is great, but product could be better.I would suggest they narrow the gap in the front of the basket so that it’s wide enough for the back slit but narrow enough to prevent shrimp from swimming through the grate. That, or make the chamber itself slightly wider.

Absolutely, unequivically, does not fit. Will not slide even a mm inside the slot before lodging firmly and bowing out the false back of the tank. I did not try to force it further. Reading other reviews, I had hoped this had been addressed and unfortunately for me I got a unit that is either out of spec, or Fluval changed their dimensions at some point. Bought the tank in late 2019.

This did not work for me at all, so very much a waste of money. It is now in my "fish" useless drawer. Did not seem to make my water any cleaner, and managed to get a couple fry killed. So I removed, and just added a small sponge filter inside my tank.

Love my Fluval flex but the stock filtration is poor at best, just this one insert in bay 1 with some filter floss and carbon packets stacked made it 85% better, opting in for trey 2 system to finish it off. Very happy with the quality and my initial purchase.