Fluval Flex 57

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Aiken Drum

Site Team
Apr 10, 2019
Derbyshire, UK
My first new tank for a couple of years. Fluval Flex 57 litre. Got a good deal on it, maybe 20% off typical prices. Just set it up, filled with water in the kitchen. Going to let it run for a couple of hours, drain it down, move it into its final resting place in the dining room, and hopfully get some substrate in there this afternoon.

More to follow as i get it scaped, cycled and stocked.

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Well, if you drink it (all), you won't be able to work on the tank - Right away anyhow, lol!

This is pretty fun looking!!! Because of this tank I spent plenty of time scouring the classifieds for cool tanks (still new tankless here).

Congrats on a new tank!

What are you going to put in there!?
The tank is for celestial pearl danios, but im hoping to fit a betta in there too. I see that combination quite often, and asking around nobody who has done that has had issues. Sure ill be the first to have a disastrous outcome though.

Im away for the weekend now, so ill get hardscape in there, try and get some plants, and refilled on Monday. I can get some cycled media in there and i think i have a bottle of ammonium chloride somewhere, so i should be able to quickly cycle it before getting fish.

I very nearly switched the purchase over to a marine set up last minute. The store was doing a deal of a fluval evo 13.5, substrate, rock, heater, 2 clownfish and a cleaner shrimp for £245. First time ive seen anywhere do a marine starter kit. Wife really wants to have some clowns too. But, last minute plans usually go awry, so i held firm.
Ah.. more planning time.

Yes, tempting. Our local SW fish store which got me into the SW hobby, has a gorgeous EVO.

Okay, was going to add a video clip and I didn't see the EVO on this clip but it has a few other picos which are lovely, if you need a few minute diversion at some point.

I was just looking at a used EVO. That seems like a good deal too. Some specials for sure! I am still needing to get my 50G +15G sump tank and stand to a new home.

That 5 Spec feature in the clip is so pretty. I have that tank holding my FW snails, maybe I should just do a pico.... in it.



I want to get an anubias in there somewhere too but cant find one at the moment.
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That's a really nice piece of DW!!!

Coffeefolia is one of my favorite Anubias, especialy the nana though in nano tanks!

Hope you find a nice one or 2. Also check for the micro sized Anubias they are adorable. Around 3-5 cm for a plant, they will grow longer like a big Anubias, the leaves are usually smaller than the top of the pencil eraser, there are several varieties of them.

Bucephalandra are great. They do not seem to like my tanks / water parameters as much as Anubias though(maybe too little calcium?) so I don't buy them very often any more.
If anyone has interest in this new tank, checked water parameters today and my fishless cycle is complete. So thats 3 weeks to complete using a little established media from another tank, which is much faster than ive achieved using bottled bacteria. Maybe 10 to 20% of the media in there is established, rest is new and the sponge block that came with the tank.

There is a lot of what looks suspiciously like cat hair in the water, given the tank has a lid that wasnt expected. There is a feeding hole and that must be how the hair is getting in, so a cover may be needed (which is extra). I think ill tape some cardboard over there short term. Maybe our cat is trying to get a drink, something to keep an eye on.

Cant get to a fish store until next monday, so ill keep adding a little ammonia until then. Plan is 8 CPD and a mystery snail, and let the danios grow out for a month or so, before adding a few otos and then a betta.
Some new fish in their new home. The store sold out of CPDs the day before, so i got a handful of zebras that will go in another tank with the other zebras when the store has CPDs (hopefully at the weekend).

The otos made very quick work of the algae in the tank. I thought they would take ages to get through everything that had built up. All the algae on the glass gone in a day. Hoping they move onto the rock now.

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Ive got 4 otos. Within a day all the algae on the glass was gone and replaced with big piles of oto poop on the substrate at the bottom of the glass. I presume algae just goes straight through their system.

I had left the light on 12 to 14 hours a day for a month before stocking to give them a good amount to eat. Need to find a replacement food now. They picked a little at an algae wafer, but ill get some veggies in there.
I thought i would post an update on how this is going.

View attachment 389696

I was hoping for a low bioload/ low water change schedule. But the tank is producing a huge amount of detritus that needs regular cleaning so im doing weekly water changes even though im seeing basically zero nitrate.

Added in an anubias plant.

The otos are all doing good. Ate all the diatoms in a matter of 48 hours, less interested in any of the other algae in the tank. They are now feeding on slices of cucumber and the occasional algae wafer.


Added in celestial pearl danios, or galaxy rasbora as they are more often called here. Added 12 in total over 2 batches, lost 2 of them but the 10 that are left are putting on some size and starting to colour up nicely now. Not sure what happened to the 2 that I lost, one went quite early when it was really small, the other im not sure when it went missing.


Also added an apple snail. It is really cool and the highlight of the tank so far. Eating his way through everything it can find. Cleaned up a lot of algae, ate an algae wafer. Going to see what he does to some cucumber shortly. Unfortunately he also sees the amazon sword as a salad bar, so i think that plant wont make it. He had a go at the anubias too, but didnt seem as keen on it. So the amazon sword will probably be swapped for another anubias.


Plans going forward. See how the amazon sword fares. Give things a couple of weeks to settle down and try and introduce a betta. Call it a day at that.

Hope the apple snail doesnt outgrow the tank (it probably will).


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What will an Apple Snail Eat?

Update time. Or as this post is titled "What will an apple snail eat?"

A shorter post would be what wont it eat.

The amazon sword is pretty much gone now. I rescued the anubias into another tank as it was going the same way, just a little slower. Tried some java fern as i have bucket loads of it, and the snail went straight at it.

So the list of vegetable matter that has gone into the tank thats not become an apple snail meal is pretty short. Marimo moss balls seem safe, so ill get some more of those. And carrot didn't seem to be on the menu.

Ill give the java fern a little longer. Given how much java fern i clear out of another tank every month i can probably keep some of that in there and replace as needed. For something with a bit of height for the background that will have to be artificial unless anyone has ideas on something that wont get chomped.
Java Fern and Anubias are a couple of the toughies!!! Hornwort and Anacharis and Water Wisteria maybe. They grow fast. Sounds like this will be a fast growing snail too, with all he's eating.
Update time.

Ive abandoned trying to keep live plants. Except for moss balls, all plants ive had in there have become snail snacks. So ive put some fairly good quality artificial silk plants in the tank.


The apple snail growth is slowing down now, maybe its fully grown now. Shell is 1.5 to 2" in diameter.

And ive added my first ever betta. I think he is the most expensive individual fish ive ever bought (and he was half the price of the betta my wife wanted to get). Seems to have settled in well. Not harrassing or being harrassed. Likes exploring the tank which is probably the most space its ever been in. I was a bit concerned about the highish flow the tanks filtration puts out, but he doesn't seem bothered by it.

A bit disappointed with the colouring on the CPDs. Not as colourful as they appear in photos. Im wondering if the black substrate, black background is something they just try and merge into.


Im not one for naming fish, but the snail is named Igor and the betta is going to be Stefano.
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