Fun with Frogs - What Happens When You Don't Clean a Filter in a Year

Since "raising tadpoles" doesn't make much sense as a title when the tadpoles have long since become frogs, allow me to introduce you to the "Fun with Frogs (& Fish!)" series! I'll be posting sporadic updates with information on the two tadpoles I decided to keep and their parents.

Say hello to Asim and Shiloh, the two males, as I later found out, that I kept. They've been living in the 20 gallon tank I was using to house the froglets in for the last year since "Raising Tadpoles" ended. That's going to be changing soon, however.

As I hinted at a few months ago, I've bought a 40 gallon breeder aquarium and plan to move all of the frogs together once I've finished working on the decor and have worked out the numbers on properly maintaining the water.

Before I can worry about any of that though, there's been a certain filter that I've needed to clean over the past year (I pulled it out of storage and plugged it in on June 29, 2018) but haven't because at first I was reliant on it for the froglets and couldn't risk a cycle and then later wasn't sure if I was planning to keep using the tank after the two frogs I kept were moved in with their parents. Since all water tests continued to return perfect results, I decided it wasn't a pressing decision. About a month ago, I decided that I'd be using the aquarium for fish after the frogs were moved (more on that in a separate entry). All of this led to me having to finally deal with the filter cleaning I had been dreading:

That means last Saturday was quite the busy day! Before I can even contemplate moving the frogs, I need to make sure the filter has been sorted out. One of the big advantages in keeping two tanks is the ability of them to function as emergency water supplies for the other should there be a sudden failure for any reason. It relieves a lot of stress knowing you always have a fully cycled filter on hand.

Now let's get into the nitty-gritty, emphasis on the gritty, and see what it looks like when you haven't cleaned your filter in over a year!

My initial impression is that it's not pretty but it's about what I was expecting. I've been avoiding feeding the young frogs worms on purpose due to the fact that the worms contain dirt and loading a filter already in need of a good cleaning with sticky black dirt is just asking for trouble. They'll be getting fed nightcrawlers for snacks once they're moved to the big tank.

Wow! It's been so long since I was inside of this filter that I completely forgot how jerry-rigged everything was. Now before I get any complaints, the reasons those sponges are mixed into the biological and chemical filtration media is explained in day 65 of my Raising Tadpoles series. I needed to jump start my cycle in a hurry and used sponges out of my large filter. Since I had to cut them to size, it meant some pieces were left over and I put them in where I could fit them.

Felt it was best to start from the bottom, which is the sponge tray, otherwise known as the mechanical filtration. The proper way to clean filtration media is to partially fill a bucket with aquarium water and wash/squeeze the media using the water. This is to avoid killing the ammonia/nitrite-consuming beneficial bacteria that inhabit the filter and keep the tank cycled. I decided to replace the contents of this tray prior to starting.

Based off a suggestion I received, I moved the water polishing pad to be directly about the coarse bio-foam sponge (although I really should have cut the middle to prevent that warping you see). The argument makes sense to me, in a proper filtration system, mechanical always comes first in an attempt to prevent unnecessary solids from becoming trapped in the biological and chemical media - neither of which are meant to filter out solid waste matter. By placing the fine water polishing pad in the bottom tray, above the coarse sponge, you receive the same quality of filtration without gunking-up your other stages of filtration unnecessarily. I'm also considering adding another sponge of moderate coarseness between the two at a later date to try refining the process a little.

Here's where I ended up running into an issue, I overestimated how much biomax I had left. My intention was to seriously beef-up the biological filtration. This is something you should especially do if you're working with an out of the box filter, companies never give enough ceramic pieces, instead they tend to give too many sponges or have you use too much carbon (which is rarely need unless your water has issues with heavy metals or other chemical contamination). For the average tank, biological media should be the heaviest concentration in your filter. We'll come back to the biomax problem in a moment.

The old water polishing pad, still in the top tray, appeared as expected. These things become saturated and look like this after about a month and should be changed regularly if you're having issues with particles floating in the water. The old bag of carbon is going to be replaced as well.

Now for the fun part - dealing with the foam filters themselves. You should never replace more than two of them at a time or you're likely to cause the tank to cycle. In this case, I'll be replacing the outer, wall sponges and keeping the inner sponges.

The water always turns black in the bucket when washing the filter media but this was the fastest I've seen it turn this dark. The foam had quite a bit of black sludge in them and that's why I always make sure I have my rubber gloves on hand during this. Nothing will harm you with skin contact, however, I still see no need to use my bare hands during this process.

This was a surprise to me, what I had thought were particularly thick layers of sludge turned out to actually be clumps of moss balls (despite the name, they're actually algae) growing inside the filter. I remember seeing some small pieces getting pulled into the filter a few moths ago when the frogs had tried to bite them but not enough to explain this. It seems the waste in the filter was quite the fertilizer.

After filling the middle tray with as many ceramic rings as I could, I added the remainder to the top tray where the water polishing pad used to be. The lack of additional biological filtration media ended up working out in my favor as you'll see in a moment.

I added one of the old sponge pieces back in with the biological media at the bottom of the tray, beneath the carbon, to protect against another cycle. I did likewise with the second tray. You can also note how dark the runoff from the filter has been on the left. I plan to remove the sponge pieces and carbon during the next filter cleaning once I can be sure the filter hasn't entered another cycle.

Here's a comparison of the rinsed sponge on the left and the unrinsed sponge on the right, note how the left has little green splotches of algae,those are the same as the dark spots on the right sponge.

The sponges are white when brand new but turn the tan color you're seeing fairly quickly, which is why it's important to make not of exactly what your replacing during maintenance - in a month, everything will look the same regardless of age.

Reassembly is extremely simple, after this, I made sure to clean the impeller and its housing, which are located in the head of the filter. One feature I particularly like about Fluval's 06 series is the ease of both detaching and reattaching the unit from the aquarium. After shutting off the unit, simply raising the gray flow valve and then popping up the red attachment lever will separate the filter from the hoses without breaking the vacuum. To reattach just put the hose connection back in place, push the red lever down to resecure the connection, ump the round, gray primer handle up and down about 4 times, and push the gray flow valve all the way down to refill the unit. After that, you can plug in the filter and adjust the flow rate as needed. To make things easier, I have mine attached to an electrical strip with a reset switch.

I wasn't kidding about there being a lot of algae in those sponges! I now have a new moss ball for my soon to be fish and shrimp tank.

On a final note, always make sure to give the sink a thorough cleaning after you finish, even with normal filter cleaning, where the worst usually looks like the lighter brown water on the right rather than the super concentrated waste on the left. Steel basins that are not used for dishes are ideal but barring that, you should have no issues using a normal sink so long as you just wash off anything that remains and wipe the sink down with soap.

The plan to avoid a cycle seems to have worked out fine for the most part, the next day the tank was testing at 0.25 ppm of ammonia, the day after that it was between 0 and 0.25 ppm, and the next two days after that it was testing barely above 0. Just in case, I delayed their feeding by two days to make sure there wouldn't be any ammonia spike. Once the fish and shrimp are moved into the tank sometime in the next few weeks, the load will be even lighter.

Links in case you'd like to check out my previous Raising Tadpoles series:
First Day
Last Day