filtration for FOWLR

oakes

New member
I'm currently setting up a 120 gallon with 75 gallon sump, still reading and researching how to design the sump itself. I plan on doing a FOWLR with preds.

Was just wondering how some of you filter your FOWLR tanks?
 
Even for FOWLR? If so then I'll just have to make one, I was under the impression that they were the best for reef tanks.
 
The basic principal of having a refugium is for nutrient export. Most people ignore refugiums on FOWLR because they are not concerned with high nitrates.

There is always a debate on high nitrates in FOWLR (whether it is really that important or not). IMO high nitrates are a sign of an overstocked tank and poorly designed setup.

Make room for a refugium and a large skimmer and you and your fish will be happier in the long run!
 
I'm currently looking at getting a SWC Extreme 200 skimmer.

In my 75gallon sump the skimmer section will roughly be 9.75", my return area is going to be 7.5" and my refugium is going to be 26.25". All will be the width of the 75gallon which is 17.5".

This is the plan for now, I'm ordering glass today and probably the skimmer today as well! Won't start construction on the sump until I get the skimmer in just to make sure it will fit where I want it too, haha.
 
That skimmer should work just fine on your size tank.

When designing you refugium you want to make that section as large as possible. Also, you may want to think about having a DSB in the sump as well, it can be part of the refugium. The DSB should be minimum 6" but the deeper the better.

Ignore the DSB for the sump if you plan on using one in your DT.
 
The plastic drawer is a bad idea. I find it funny that guy spent so much money and effort on a beautiful DT tank and then cheeped out on the sump. How is the water suppose to flow through the drawers evenly? I can also see that thing clogging in no time!

I wont talk about the media he is using as most of it will be a nitrate trap and a bad idea. Personally I would rather just use the Rubbermaid container and figure out a way to section it for the skimmer/refugium/return pump.
 
I think you need to think through the issue of a deep sandbed in the refugium (or the display). Not a good idea if you are thinking of having a bacterial driven system. The same holds true wth having a lit refugium which is also generally not a good idea with a bacterial driven system.

When I refer to a bacterial driven system, I mean a system where you carbon dose (liquid via vodka or vinegar or solid with pellets) and/or dose live bacteria. The modern trend in aquaria is to not have a deep sandbed, nor a lit refugium and instead adopt a bacterial driven approach. Take a look at the chemistry forum and the many threads on solid carbon pellet products and liquid carbon dosing.

I have a bacterial driven system and a refugium. I do not light my refugium and have no sand in the refugium. The reason a lit refugium is a bad idea when you have a bacterial driven system is the macro algae is unable to survive and grow because the bacteria consume too many nutrients. As such, the macro algae usually slowly withers away and releases nutrients into the system making the macro algae counter-productive. Likewise, deep sanbeds do not work well with a bacterial driven system because large amounts of bacterial mass accumulates in the sandbed fed by the carbon and create problems with trapped gases and other bi-products from the bacteria. I use my refugium in my fowlr exclusively as a place to have more rock for biofiltration and grow pods and other microfauna. I also have a very shallow sandbed in the display which I strongly recommend you also have in the display if you feel you must have a sandbed in the display, otherwise, it is even better to go bare bottom in the display. Remember, in virtually all fowlrs you can have very few inverts in the display to act as a clean up crew because they will get eaten by your fish. As such, a sandbed, particularlly in a fowlr, has a high probability of becomming a nutrient trap because there will be no critters in the sand to eat the organic waste which accumulates.

Finally, a skimmer is the most important item of equipment in a fowlr and even more important in a bacterial driven system. The skimmer, other than water changes, will be your primary way to export nutrients. The SWC 200 you are thinking of purchasing is a good option for your sized system. I invite you to also take a look at the SRO line of skimmers which include a better and more reliable pump and a more modern body style in the form of a cone hybrid. The reason I suggest this line is that they are competitively priced to the skimmer you are considering and are a product line that Coralvue next introduced after the extreme design you are now considering. To me, I would go with the more modern body design and better pump found in the SROs which are close in price to what you are considering in the SWC 200.
 
Last edited:
I think you need to think through the issue of a deep sandbed in the refugium (or the display). Not a good idea if you are thinking of having a bacterial driven system. The same holds true wth having a lit refugium which is also generally not a good idea with a bacterial driven system.

When I refer to a bacterial driven system, I mean a system where you carbon dose (liquid via vodka or vinegar or solid with pellets) and/or dose live bacteria. The modern trend in aquaria is to not have a deep sandbed, nor a lit refugium and instead adopt a bacterial driven approach. Take a look at the chemistry forum and the many threads on solid carbon pellet products and liquid carbon dosing.

I have a bacterial driven system and a refugium. I do not light my refugium and have no sand in the refugium. I use my refugium in my fowlr exclusively as a place to have more rock for biofiltration and grow pods and other microfauna. I also have a very shallow sandbed in the display which I strongly recommend you also have in the display if you feel you must have a sandbed in the display, otherwise, it is even better to go bare bottom in the display. Remember, in virtually all fowlrs you can have very few inverts in the display to act as a clean up crew because they will get eaten by your fish. As such, a sandbed, particularlly in a fowlr, has a high probability of becomming a nutrient trap because there will be no critters in the sand to eat the organic waste which accumulates.

You bring up a valid point, however the orginal poster did not say he was going have just aggressive fish that would devour any CUC. A bacteria driven system is a relatively new method and as far as I am concerned I have not seen enough evidence on the bio-pellets to back up that method. Vodka dosing......maybe, but this can be a disaster for a new hobbyist (no idea if the original poster is experienced or not).

Here is an article that I find to be a good read and has some actual scientific evidence:

http://www.ronshimek.com/deep_sand_beds.html

If you have a DSB in a refugium or even one better a RDSB how are fish going to eat the critters that stir up the top layer????

I ask this question to the poster. Do you want a bacterial driven system? What type of fish are you planing to stock your tank with?

I think there is justification for both types of systems.....the stock list and experience should be the deciding factors
 
You bring up a valid point, however the orginal poster did not say he was going have just aggressive fish that would devour any CUC. A bacteria driven system is a relatively new method and as far as I am concerned I have not seen enough evidence on the bio-pellets to back up that method. Vodka dosing......maybe, but this can be a disaster for a new hobbyist (no idea if the original poster is experienced or not).

Here is an article that I find to be a good read and has some actual scientific evidence:

http://www.ronshimek.com/deep_sand_beds.html

If you have a DSB in a refugium or even one better a RDSB how are fish going to eat the critters that stir up the top layer????

I ask this question to the poster. Do you want a bacterial driven system? What type of fish are you planing to stock your tank with?

I think there is justification for both types of systems.....the stock list and experience should be the deciding factors

You also make some good points. However, I do have to strongly disagree with any general characterization that a bacterial driven system is something new and/or untested, as well as being difficult to implement. Certainly, solid carbon dosing is new and still somewhat unproven, although after closely following all the pellet threads I will assert that most people have great success with the pellets. However, liquid carbon dosing at this point is a tried and true reliable method to export nutrients which many very conservative and very experienced reefers here, such Randy Holmes Farley, TMZ, Bertoni, and others, use with great success. Moreover, there really is very little risk to the bacterial driven approach as long as you dose in accordance wth the Reefkeeping article which provides very easy to understand directions merely involving measuring nitrate and dosing appropriate amounts of the liquid carbon. Indeed, carbon dosing in a fowlr has hardly any risk because you have no corals to worry about which could not respond well to the carbon dosing. Really, the only risk you run in a fowlr with the bacterial driven approach is oxygen deprivation which only occurs with extreme carbon overdosing and is usually completely avoided even with extreme overdosing by the oxygen created by an appropriately sized skimmer.

Many people have had many problems with a deep sandbed over time becomming fowl and actually becomming a nutrient trap. I have tried both, and my opinion is that a bacterial driven approach is far better at controling nutrients, but obviously that is a matter of opinion. Generally, I do think it is very fair to say that the overwhelming majority of new systems today are not set up with deep sandbeds and many (if not most of them) ultimately elect to adopt the bacterial driven approach. This is especially true in fowlrs which are heavily stocked. I rarely see today any heavily stocked fowlr which is not bacterially driven.
 
Last edited:
Thanks for all the post and suggestions! That's what I was looking for..To answer a couple quick questions while I have time..

I am new to salt, this will be my first SW tank. That's why I was going with preds and no corals just so I could get a better understanding of it all. I've run larger FW with sumps but I know things go different with SW in the sump area.

For fish, what I was thinking of getting might change as my LFS has an undulated trigger that they have hanging out in their LR tank because he's suppose to be real mean, so if I can work a deal with them I might take this one off their hands and work my fish selection around him.

I was thinking of having a 1" to 1.5" sand bed in the main tank and was thinking of a DSB in the refuge.
 
Thanks for all the post and suggestions! That's what I was looking for..To answer a couple quick questions while I have time..

I am new to salt, this will be my first SW tank. That's why I was going with preds and no corals just so I could get a better understanding of it all. I've run larger FW with sumps but I know things go different with SW in the sump area.

For fish, what I was thinking of getting might change as my LFS has an undulated trigger that they have hanging out in their LR tank because he's suppose to be real mean, so if I can work a deal with them I might take this one off their hands and work my fish selection around him.

I was thinking of having a 1" to 1.5" sand bed in the main tank and was thinking of a DSB in the refuge.


If you purchase the undulated trigger, you pretty much can forget about any tankmates, other than perhaps a certain few other very aggressive fish -- most of which will not fit in your system. Moreover, you cannot have any inverts in the display, and therefore, I recommend only a sandbed, if you must have one, in the display of .5 inches or less. As far as a DSB in the refugium, my view of DSBs is stated above, and I think in the end and particularlly as they age they cause many more problems than good in terms of nutrient export.
 
Well I think you have all the information to make your own decisions regarding DSB or a bacterial driven system. I didn't mean to say that all bacteria driven systems are new (I was refereing to the bio-pellets only). Should of made that clearer. Liquid Carbon dosing (vodka....) seems to be a lot safer with FOWLR systems but again I would suggest that this be done by someone with some experience.

Stuart, If you could point me to some systems that have been running the bio-pellets for an extended period of time (1+ years) with success then I would be more inclined to recommend them.

I dont think either approach is wrong as there is evidence that both of these systems can work.

Nutrient export is always an on going debate in almost all reef/FOWLR forums and everyone has there own recommendations and opinions based on there experience.

Always good to get the brain thinking.....great discussion Stuart!
 
Last edited:
I'll read up more on all the above later..

But if I do not get this undulated trigger fish my stocklist might look like something below..

Snowflake eel, humu picasso trigger, volitan trigger or variant, puffer of some sort. Everything won't be added at the same time but that's just my thoughts at the moment.

I'll have plenty of time to rethink my fish selection before I set up the tanks and while I wait for them to cycle.
 
Well I think you have all the information to make your own decisions regarding DSB or a bacterial driven system. I didn't mean to say that all bacteria driven systems are new (I was refereing to the bio-pellets only). Should of made that clearer. Liquid Carbon dosing (vodka....) seems to be a lot safer with FOWLR systems but again I would suggest that this be done by someone with some experience.

Stuart, If you could point me to some systems that have been running the bio-pellets for an extended period of time (1+ years) with success then I would be more inclined to recommend them.

I dont think either approach is wrong as there is evidence that both of these systems can work.

Nutrient export is always an on going debate in almost all reef/FOWLR forums and everyone has there own recommendations and opinions based on there experience.

Always good to get the brain thinking.....great discussion Stuart!


Agree, and I always enjoy having an intelligent civil discussion about issues like these with someone, like yourself, who has command of the topic. As far as pointing to any long term success with the pellets, about 1 year and change is the longest I have ever heard of anyone using them so I agree that a long term track record with these has yet to be established.
 
Last edited:
I'll read up more on all the above later..

But if I do not get this undulated trigger fish my stocklist might look like something below..

Snowflake eel, humu picasso trigger, volitan trigger or variant, puffer of some sort. Everything won't be added at the same time but that's just my thoughts at the moment.

I'll have plenty of time to rethink my fish selection before I set up the tanks and while I wait for them to cycle.


I could respond to these choices, but it seems like you have couple of the fish names mixed up. Read some more about these fish and the various filtration approaches described above. Once you think you are sure as to which fish you would like to keep, post them, and I, as I am sure others here, would be happy to provide you with some input. As Hydrologist pointed out above, it is better to first decide what livestock you wish to keep and then to build the system around how to best meet their needs.
 
I could respond to these choices, but it seems like you have couple of the fish names mixed up. Read some more about these fish and the various filtration approaches described above. Once you think you are sure as to which fish you would like to keep, post them, and I, as I am sure others here, would be happy to provide you with some input. As Hydrologist pointed out above, it is better to first decide what livestock you wish to keep and then to build the system around how to best meet their needs.

Names mixed up? Could you expand this some more? I mean I am new to salt and I believe these fish are semi-aggressive to aggressive, so if they will not mix please let me know. But like I said nothing is set in stone at the moment. Nothing for this setup will start construction until atleast next weekend when I have my skimmer to build my sump around.
 
Names mixed up? Could you expand this some more? I mean I am new to salt and I believe these fish are semi-aggressive to aggressive, so if they will not mix please let me know. But like I said nothing is set in stone at the moment. Nothing for this setup will start construction until atleast next weekend when I have my skimmer to build my sump around.


Sure. I am pretty sure that there no fish seen in the hobby with the common name "Volitan Trigger", or for that matter, any "variant" of this species. :lolspin:

If what you mean here is what you want to stock is a snowflake eel, humu picasso trigger, volitan llionfish or variant, and a puffer of some sort then these stocking choices are fraught with problems and special considerations. First, you can never house the huma and the lion in the same tank b/c the lion will likely be killed (see sticky at top of this forum). Second, in my opinion your tank is too small for a picasso other than when the picasso is very small b/c they become bullies in small systems as they age. Do a search in the aggressive fish forum for threads with the title "picasso", and you will find a bunch of recent threads here where this was discussed in great detail. Third, you need to be aware that housing the eel will require some special care. Your tank must not have any openings, or the eel will escape and could die if not discovered and returned to the tank quick enough. Also, you will need to target feed the eel with a feeding stick and be very careful whenever you place your hands in the tank. Fourth, all puffers are not appropriate for this sized system, and I would stick with a dogface or toby. Lastly, all of these fish involve a massive bioload that would be quite a challenge to maintain. Tank could easily wind up being an algae farm.
 
Last edited:
Back
Top