Confused - Is My Filter Actually Filtering?

[New tropical gal]

Hi all

I’m relatively new to the hobby of tropical fish keeping, I started out with a Biorb which had appaling filtration and recently splashed out on a new tank. I’ve purchased a 100 litre cubic tank with built in underwater filtration. It’s said to be a good build quality and spec – it’s Rena.

I plan to run a tropical tank containing 50% fish and 50% natural plants. To accommodate the same when setting up my tank I layered Laterite on the base (for the plants) and added a further layer of gravel. I then filled my tank with water – oh dear, despite washing the gravel thoroughly the water became pure white and cloudy for days... My ‘filter’ seemingly failed to filter. I then drained 50% of the water and added some Nutrafin Clearfast (which worked a treat).

A few days later I added my first fish: two small tetras. I’m monitoring the water parameters etc. closely and carry out water changes as and when necessary.

Today the water is ‘misty’. There are lots of particles floating around – akin to dust. The surface of the water is filled with a dirty looking film (which I cant siphon; I can only siphon underneath the surface).
Surely the filter should be stopping the ‘dusty’ effect currently in place? I feel like my filter isn’t filtering which is disappointing me. That said, this is only the second tank I’ve owned and the first was quite poor so I don’t have much to compare to.

Please could you advise whether this is normal or whether my filter is failing me?
Your help is hugely appreciated – thank you

Kate

 

[OldMan47]

Welcome to the forum tropical gal.
You say that you have an underwater filter. Is it one of the ones that you put your gravel on top of or is it one that sits somewhere in the tank with some sponges and a pump in it? If it is the first type, an undergravel filter, it will not work when you have laterite directly on top of the filter plate. An undergravel filter uses the gravel itself as the filter medium. Since the laterite is below the gravel, it has no chance to filter out the laterite dust. Laterite is very fertile but is a dirty substrate to use until the plants roots get into it to hold it in place properly. That is why people put a layer of gravel over the top of it. I have only used the Rena externals and they work great, I have no idea what they make in terms of underwater filters.

 

[New tropical gal]

Welcome to the forum tropical gal.
You say that you have an underwater filter. Is it one of the ones that you put your gravel on top of or is it one that sits somewhere in the tank with some sponges and a pump in it? If it is the first type, an undergravel filter, it will not work when you have laterite directly on top of the filter plate. An undergravel filter uses the gravel itself as the filter medium. Since the laterite is below the gravel, it has no chance to filter out the laterite dust. Laterite is very fertile but is a dirty substrate to use until the plants roots get into it to hold it in place properly. That is why people put a layer of gravel over the top of it. I have only used the Rena externals and they work great, I have no idea what they make in terms of underwater filters.

Thank you for your assistance & for the warm welcome.

It is a cube shaped aquarium with a built in filter column in the corner, contains a water pump (which doesnt feel overly powerful when I place my hand over it). Definitely not an under gravel filter.

Should water pumps be very powerful? Does your water contain lots of 'dusty' particles? Perhaps matters will improve when I insert my plants this weekend.

 

[OldMan47]

You can expect that stirring the laterite, by planting plants, will give a burst of suspended material in the water.
What kind of filter media are in that filter? There should be sponge or filter floss or something to actually filter the water. The circulation often indicates whether or not the filter media are becoming plugged. My Fluval sponge type internal, a model 4+, almost stops flowing water as it plugs up and pumps like crazy when it is clean. The same happens with the externals that I have. The flow change is less noticeable when I am using a sponge with a separate power head. Sponges and box filters that use air for power are notably slowed when the media is dirty.

 

[New tropical gal]

You can expect that stirring the laterite, by planting plants, will give a burst of suspended material in the water.
What kind of filter media are in that filter? There should be sponge or filter floss or something to actually filter the water. The circulation often indicates whether or not the filter media are becoming plugged. My Fluval sponge type internal, a model 4+, almost stops flowing water as it plugs up and pumps like crazy when it is clean. The same happens with the externals that I have. The flow change is less noticeable when I am using a sponge with a separate power head. Sponges and box filters that use air for power are notably slowed when the media is dirty.

I see. At present the filter seems to work on three levels: foam in the first compartment, 'crystal dose' cartridges in the second (said to remove odours and cloudiness), and carbon stars in the final compartment. I installed an air pump too whcih seems to improve circulation.

I'll keep you posted with my progress

 

[OldMan47]

The air will definitely improve water circulation. The crystal dose sounds like it is probably a chemical filter and the carbon is definitely a chemical filter. I think I would remove the 'crystal dose' and use the space for another sponge if you can get one to fit properly. If you do that, stack the sponges first and last in the flow path and put the carbon in the middle. If your flow is much slower than it started out, you may have a layer of laterite dust on that sponge restricting water flow.

 

[New tropical gal]

The air will definitely improve water circulation. The crystal dose sounds like it is probably a chemical filter and the carbon is definitely a chemical filter. I think I would remove the 'crystal dose' and use the space for another sponge if you can get one to fit properly. If you do that, stack the sponges first and last in the flow path and put the carbon in the middle. If your flow is much slower than it started out, you may have a layer of laterite dust on that sponge restricting water flow.

Thanks for the tip - I'll check the sponge for signs of clogging and will see if I can find something to fit in the middle compartment in place of the crystal dose.

Many thanks to you for your help.

 

[waterdrop]

Hi Kate and welcome to the beginners section!

I'm going to try and make a start on your question. You've found yourself at a good hobbyist forum though and so there are a whole host of things the members can potentially help you with at this stage of your learning. The filter question is key but is not the only one that is important for you at this stage.

The cloudiness in your tank is actually probably not important compared to other things. Its most likely what we call a "bacterial bloom" and is made up of millions of "heterotrophic bacteria" that have found some things to eat because of the sealant that a new tank is built with. They will go away. The real issue for you is actually a completely different set of bacteria, autotrophic bacteria, that you can't see but that will populate the aquarium filter and are key to the "biofilter" function. One of the main topics of this forum is helping newcomers learn all about the importance of the biofilter and the ways to create and maintain one and how to understand it.

UGFs (Undergravel Filters) My short comments: Many of us feel that for beginners, these filters are difficult and, in a way, have been superseded by newer technology. Depending on the tank size and budget, external cannister filters, HOB (Hang on Back filters) or internal filters are now more commonly used.

My longer version of comments: UGFs can be run in either direction, pulling water through the gravel and then up and out the side pipes (called a normal UGF) or the water can be pumped down the pipes and pushed out into the aquarium through the gravel (called a RUGF, for Reverse Undergravel Filter.) The UGF/RUGF is and old and established type of filter and one of the least expensive technologies. By providing ample surface area (the gravel) and by moving oxygenated water and ammonia across these surfaces (the pumping of water through the pipes to pull or push it through the undergravel plates) a good biological filter can be created. The gravel also serves as the mechanical filtration, trapping particles, for better or worse. Besides biological and mechanical, there is a third function of filters, the optional special function of chemical filtration. Examples of this are carbon, zeolite, crushed coral, peat and some other things. UGF/RUGF filters have no provision for this function. UGF/RUGF filters are relatively poor at mechanical filtration in that the lack of a "filter box" does not help with excess partical removal, as it would with other filter types.

One of the big problems with UGF/RUGFs is that they are hard to clean (the area under the plates becomes loaded with debris) because getting under the plates disturbs the whole aquarium. By contrast, other filter types can easily undergo the normal monthly filter clean that keeps an aquarium running nicely. Rooted plants are also a difficulty, due both to roots getting down in the plate openings and because rooted plants just don't do well usually in UGF/RUGF type setups. A workaround is to use all ferns and floating plants, which can work quite nicely in low-light inexpensive beginner setups.

One tidbit I've learned about UGF maintenance is that if you can clear away some of the gravel, place a siphon hose directly on the plate slots and get good suction, sometimes the heavy debris under the plate can be sucked out and the UGF can be kept in good working order. Another tidbit is that the gravel needs to be just the right depth (not sure how to define that) and needs to be fairly flat and even, rather than having landscaping hills etc. There are probably other bits I've forgotten but hopefully this will give you some info to get started. I'd say its important for you to decide if you're going to stick with this filter for purchase another type as getting the right sort of filter is a prerequisite to fishless cycling, which is a prerequisite to a biofilter, which is a prerequisite to fish!

~~waterdrop~~

 

[waterdrop]

Ha!, well scratch all that, I mistook your comment of underwater filter to mean an undergravel filter and obviously its not that type. Your corner filter sounds much better and I agree with OM47 that the chemical portions should be replaced with more sponge or other biological media. It sounds like you are in a Fish-In cycle (at least assuming the tank is less than a month running or so?) so I wonder what sort of water testing kit you have? That usually is the first bit of gear we need for determining the state of the biofilter that the fish need.

~~waterdrop~~

 

[OldMan47]

I think we caught this one at the fishless stage WD. Once in a while we get lucky I guess.

 

[drobbyb]

Have a read at the topics in OM47's signature, specifically fishless cycle and beginner's resource center. Reading those topics will get you squared away with all the basic information you will need, and this will allow us to answer any other questions you might have.

One of the most important tools that a new fishkeeper (and experienced ones too) will need is a good quality liquid reagent based test kit like the API Master Test Kit. This will give you a few tools to monitor your fishless cycle and will give you some sense of where you are in that cycle.