Advice on Regular water changes etc? updated

[Naughts]

The brown goo is exactly what it sounds like, and the fish are in an enclosed system.
Imagine having your air pass through a sewer and you will see why it us good practice to clean the filter media regularly!

Cleaning the filter media also prevents the filter impeller and sponges becoming clogged by a build up of gunk which would otherwise slow it down or stop it working.

In an established tank there are beneficial bacteria firmly attached to the substrate, on the glass, on ornaments, plants...You will not crash a cycle by rinsing filter media in old tank water nor by doing 50-75% water changes.

 

[justinhill]

Is it possible (he asked, trying to be the diplomat) that there's more flexibility when you're talking about large (300L plus) tanks with complex external filters, compared to small (100L or less) tanks with basic submerged filters? Even in my still very limited experience I have already seen that pump throughput is quite quickly impaired as the filter sponges get full, with my fairly basic filter/pump unit.

 

[kwi]

It’s not a matter of votes, this is worth considering from Swiss Tropicals:

Biofilms and Biofloc​

From the Poret Foam Supplier (Swiss Tropicals)

“The purpose of the filter media is not to filter the water as is often assumed. The filter media serves as the habitat for a vast array of microorganisms that include bacteria, archaea, worms, ciliates, flagellates, and many others. These microorganisms live in a community that is based on biofilms. The biofilms are created by bacteria that secret extracellular polymeric substance (EPS), which is often called “slime”. The community forms a bioreactor that processes the waste and turns it into food and energy for its members, and ultimately into organic or inorganic products that are then used by plants, evaporates, or is removed by water changes. It takes a considerable amount of time to establish this “filter community”; consequently, it is very important not to disturb it unless absolutely necessary. The brown filter sludge in a filter is for the most part alive and not simply waste. Removing this mud does more harm than good.

And this from a respected supplier who really care about effective filtration.

It's also an old way of thinking, alongside the dirty water is good water, and minimal water changes.

 

[P J]

The brown goo is exactly what it sounds like, and the fish are in an enclosed system.
Imagine having your air pass through a sewer and you will see why it us good practice to clean the filter media regularly!

Cleaning the filter media also prevents the filter impeller and sponges becoming clogged by a build up of gunk which would otherwise slow it down or stop it working.

In an established tank there are beneficial bacteria firmly attached to the substrate, on the glass, on ornaments, plants...You will not crash a cycle by rinsing filter media in old tank water nor by doing 50-75% water changes.

Filters can be unclogged without damage to the biofilm - so not an issue. The bacteria attached to the substrate and other items needs an oxygenated water flow over it to be an effective biological filter.

 

[Naughts]

Filters can be unclogged without damage to the biofilm -

I'm not sure what you mean here.

. The bacteria attached to the substrate and other items needs an oxygenated water flow over it to be an effective biological filter.

Many of us here clean the filter media regularly and never have detectable ammonia or nitrite so we can conclude that the water flow and oxygen levels in a filtered aquarium are sufficient to maintain beneficial bacteria.

With a new tank we recommend the filter is left alone for 6-8 weeks.

 

[Essjay]

I would not necessarily believe anything written by someone who wants to sell something. Manufacturers often sell things which are useless or even dangerous while extolling their virtues.

 

[justinhill]

I would not necessarily believe anything written by someone who wants to sell something. Manufacturers often sell things which are useless or even dangerous while extolling their virtues.

Now that I understand. I know next to nothing about fish keeping (clearly) but in my business (I'm a recording engineer and producer of 30 years standing) we are bombarded with "wisdom" from an industry that wants to get us all to buy into their products and their workflows.

Unfortunately, new engineers are also bombarded with similar "wisdom" from people who have themselves bought into a particular workflow and feel the need to defend their choices as 'gospel'. This leads to people spending lots of money on systems they believe will solve all their problems and make them great engineers when actually what they needed was to better understand the fundamental principles of how stuff works and learn to use it properly.

Who'd have thought that fish keeping and audio engineering would have something in common...

 

[Pidge1992]

I have a fully cycled 55 gal tank, I have a HOB filter and a sponge filter. My ammonia is 0 my nitrite 0 and my nitrate is never over 40. Water is crystal clear. I change 1/3 of my water and vacuum the substrate every other week now. I use a python water changer (this thing was life altering lol) and my fish are super healthy. Your tank is smaller and sounds like it’s less mature than mine. I’d do weekly changes of 25% and clean the filters in old tank water every other week to maintain good water flow. If I don’t clean the goop out of my HOB every other week it gets clogged. I don’t have to clean my sponge nearly as often.

 

[Slaphppy7]

It’s not a matter of votes, this is worth considering from Swiss Tropicals:

Biofilms and Biofloc​

From the Poret Foam Supplier (Swiss Tropicals)

“The purpose of the filter media is not to filter the water as is often assumed. The filter media serves as the habitat for a vast array of microorganisms that include bacteria, archaea, worms, ciliates, flagellates, and many others. These microorganisms live in a community that is based on biofilms. The biofilms are created by bacteria that secret extracellular polymeric substance (EPS), which is often called “slime”. The community forms a bioreactor that processes the waste and turns it into food and energy for its members, and ultimately into organic or inorganic products that are then used by plants, evaporates, or is removed by water changes. It takes a considerable amount of time to establish this “filter community”; consequently, it is very important not to disturb it unless absolutely necessary. The brown filter sludge in a filter is for the most part alive and not simply waste. Removing this mud does more harm than good.

And this from a respected supplier who really care about effective filtration.

Yeah....I'm going to take this with a block of salt...

 

[Kuriuskitten]

Hmm. This is an interesting thread. I guess I'm a minimalist. I test my water twice a week and I usually only top off for evaporation. Once a month I'll vacuum substrate, replace whatever water I lose doing that.
It really depends on an individual tank, how stocked it is, what kind of fish, filtration type, feedings, etc.
Just do what it takes to keep water values optimal for your fish, and stick with it.

 

[Essjay]

What is your nitrate like? That usually builds up higher than the maximum recommended level of 20 ppm with fewer water changes unless the tank is heavily planted.


Be careful topping up if you use tap water. Only water leaves the tnak with evaporation; everything dissolved in the water stays in the tank and topping up with tap water gradually increases the level of the dissolved things. For example, the hardness minerals build up so the hardness of the tank gradually increases over time. Using RO or another forum of pure water for topping up does not do this.

 

[Kuriuskitten]

What is your nitrate like? That usually builds up higher than the maximum recommended level of 20 ppm with fewer water changes unless the tank is heavily planted.


Be careful topping up if you use tap water. Only water leaves the tnak with evaporation; everything dissolved in the water stays in the tank and topping up with tap water gradually increases the level of the dissolved things. For example, the hardness minerals build up so the hardness of the tank gradually increases over time. Using RO or another forum of pure water for topping up does not do this.

Nitrates are 5ppm or less usually. Tank is planted, but not very heavily.
I do use tap, but it's quite soft, so the minerals don't really build up.

 

[justinhill]

So I left things alone for a week, kept an eye on my water test results (all good and stable) and then this morning changed about 35% of the water with temperature-matched tap water dosed with Stress Coat. I scraped the crud off the filter sponges gently in used tank water while I rinsed the filter body itself in warm tap water to clear the inlets.

I have now bought a Nitrate test kit and used it for the first time just before I did the water change. It came out between 30 and 40 ppm as best as I can tell - I actually don't find it very easy comparing the water colour with the chart (must be my eyes!)

Thanks for all your advice and suggestions. This (I hope) will now be my weekly routine, but we'll see how the test results look as the week progresses.

 

[Essjay]

First - is this a liquid nitrate tester and if so, did you shake the bottle then the tube like the instructions say? Liquid testers have 2 or sometimes 3 bottles and one of them needs to be shaken well because one of the reagents settles on the bottom of the bottle and it needs to be shaken to get that reagent back into the liquid.


Next - can you test your tap water for nitrate, please. Some areas have quite a bit of nitrate in the tap water and we need to know if your nitrate level is coming into the tank in your tap water or if it's being made by the beneficial bacteria. [UK legislation allows up to 50 ppm nitrate in drinking water]

 

[justinhill]

First - is this a liquid nitrate tester and if so, did you shake the bottle then the tube like the instructions say? Liquid testers have 2 or sometimes 3 bottles and one of them needs to be shaken well because one of the reagents settles on the bottom of the bottle and it needs to be shaken to get that reagent back into the liquid.


Next - can you test your tap water for nitrate, please. Some areas have quite a bit of nitrate in the tap water and we need to know if your nitrate level is coming into the tank in your tap water or if it's being made by the beneficial bacteria. [UK legislation allows up to 50 ppm nitrate in drinking water]

I will test the tap water and report. Actually I suspect that first reading was wrong due to poor technique. I just tested nitrate again, after the water change, and it's less than 10ppm for sure, maybe less than 5ppm. That's come down too much for 35% water change. It's an API kit, with two reagents, and I'm following the instructions re shaking up and down...