Confusion over filtration!

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Tortle

Aquarium Advice Apprentice
Joined
Mar 2, 2016
Messages
11
Location
Hampshire, UK
Hi!
I am looking to upgrade my 20L marine tank to a 100L. The problem is that this tank is the top of a stack of three so I have no room to add a sump or have any kind of filter that needs space outside the tank. I am intending to section off one corner of the tank which will hold all equipment and am planning on only having pulsing xenia, mushrooms and whatever else appears on the rock, along with one fish (will be asking questions about that later too!!)

I have been looking for advice with regards to what kind of filter and filter media I need, or, indeed, if I need any and have just been confusing myself!
I have been reading lots of things that say all I need is the live rock, sand, skimmer and powerheads for water flow, but is this ok for a 100L? Do I need any other kind of filter media?

If anyone can offer me advice or their own experiences this would be greatly appreciated! I can build, run, change and adapt freshwater filters til the proverbial dairy herd gets here but my only experience with marine has been in the last year and on a tiny scale! I don't do small tanks so have been itching to upgrade the 20L for ages - now a tank is free and I need to get it started!!
Thanks in advance!

Just realised that gallons might be more useful for most members...20L = 4.5G (5.2 US G) 100L = 22G (26.5 US G) Think those conversions are right...!
 
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The main filtration in saltwater is the rock and sand in the tank. As long as you are feeding minimally, have proper flow, and use ro/di water, you can easily get away with using HOB equipment to filter your tank. For a HOB filter I would want to use one rated much higher than the tank, but in terms of filter media it always ends up varying on what is going on in the tank itself...won't know that until the system is running and maturing.
You may also want to consider a skimmer. Though you can get away without one, as small systems can easily be managed with water changes to address issues, they are always beneficial as they remove waste from the water column before it can break down in the nitrate cycle.
 
Thanks for your reply, very helpful, but I may have some more questions...!

Is HOB Hang On Back? It's not something I'm familiar with, and I don't think I would have the space, due to the tank being against the wall.

I was planning on siliconing perspex at one end or corner of the tank to create a space where I can place powerhead, heater etc - would this work in place of HOB? I would probably also do a smaller one at the other end to enable two powerheads to be used.

Do you think I would be better to set up the tank with live rock and sand, get the powerheads working and then see what else I needed?

In my small marine I currently have a mini external - not the best for marine I know - but this has been working really well so far (tank has been running for just under a year) with just the standard ceramic noodles and filter sponge. This was before I really started to look into it properly so with an upgrade just want to make sure I get it right!

Am I right in thinking a protein skimmer needs to be outside the tank - or at least part of it - as well?

Sorry for all the questions!
 
Yes, hob stands for hang on back.
I don't see where a small place is going to replace physical filtration. It would be just like the skimmer, as it would hang off the back of the tank.


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Anyway the setup can be moved out a little from the wall?You would only need a few inches to be able to use hob equipment .


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To be fair there is no reason why the tanks can't be moved, it just means draining the other two tanks down to do it, which I was trying to avoid to be honest!!

So I could do powerhead at one end and an HOB at the other and this would provide me with filtration and enough flow? Would an HOB do a similar job to a skimmer if positioned correctly or, as it is not a big tank, would the work that a skimmer do not be so important?
Thanks!
 
HOB filter on one end and a power head on the other would be fine,but ideally you also need at least one and a half lbs. of live rock per gallon.
On that size tank if you do a partial water change weekly you would not need a skimmer.

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Thats brilliant, thankyou so much for your help!
If my maths is right then im looking at about 37lb of live rock which I think is about 16kg. This could take some saving up!!
Thanks for your time and help on this.
I know it will be a long while til im ready for any livestock but what kind of single fish could I keep in this size tank? I just want one specimen fish and really like fuzzy dwarf lionfish but would this size be too small for one? If so, what alternatives would there be?
 
Id say 26g is to small for a dwarf lion imo. But if your looking for one interesting fish an angler would work, and are some of the coolest looking creatures on the planet. The striated and wartskin are my 2 favorites.

You also don't need 1.5 lbs of rock per gal, 1lb is fine. And a skimmer isn't necessary on this size tank. And no a hob filter doesn't do the same job as a skimmer, but because larger percentage wcs are easier on nano tanks they aren't really necessary. 25% weekly will keep you right where you want your params and it's only 6 gallons or so


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Id say 26g is to small for a dwarf lion imo. But if your looking for one interesting fish an angler would work, and are some of the coolest looking creatures on the planet. The striated and wartskin are my 2 favorites.

You also don't need 1.5 lbs of rock per gal, 1lb is fine. And a skimmer isn't necessary on this size tank. And no a hob filter doesn't do the same job as a skimmer, but because larger percentage wcs are easier on nano tanks they aren't really necessary. 25% weekly will keep you right where you want your params and it's only 6 gallons or so


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Agree with you on the stocking but not on the amount of rock.While one lb per gallon may work
It is not sufficient without having a skimmer or doing the large weekly water changes.

I run a 20 gallon high reef with one powerhead and Fluval hob that I use media in.I have one and a half lbs of rock and three to four inch sand bed.I only do a weekly water change of one gallon
And have zero nitrates.
ImageUploadedByAquarium Advice1457111601.597758.jpg


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Ok, so this is looking easier than I thought then - one powerhead, one HOB and plenty of live rock and sand and all should be good!
Should I stick with the filter media that I assume comes with a HOB, or should I remove it and replace with something else?

Oh, and I just looked up the fish you recommended - oh my god, little bit in love! I think I've seen these for sale but usually really tiny. Ridiculously cute - maybe even better than a lionfish! I take it it would still be only one in a tank, due to their eventual size and, I'm assuming from the look of them, aggressiveness?!!
 
Just had a quick scout online and it seems that Aquaclears are rated quite highly. I can get an Aquaclear 50 for between £30 and £40 and this does 750 lph and is rated for tanks up to 190L - would this be suitable or would I need to find one that does more? If it needs to be bigger then recommendations on cheaper, but also efficient HOBs would be appreciated!!
 
It would be,keep the sponge and carbon pouch but lose the bio balls.Get the Chemi-pure elite to use in place of them.It comes in a pouch to put in the hob filter.


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Awesome! That's brilliant, I will be getting one next payday methinks!
Thank you all so much for your help and advice, will keep you updated how the tank goes and I'm afraid I will probably also bother you with questions again soon enough!!
 
Just seen this thread. Why not use the top tank as the saltwater and you could use the bottom as a display fuge. Have a deeper sandbed and lots of macro algeas. You could drill the top tank and install overflow or buy a hob overflow drain down to bottom tank and put a return pump into bottom tank. Lot of work. But it would look nice.

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Well I could do that but there's some axolotls that might be a bit put out getting kicked out their tank!! The other two tanks in the stack are inhabited so unfortunately that is not an option!!
 
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