View Full Version : Glass Cleaning

01-15-2016, 04:11 PM
Quote Originally Posted by SlimmSnake View Post
Hi... I've read on a number of other posts, when doing regular water changes, experienced people say they always wipe down the glass of the tank every time. An obvious reason to wipe the glass seems to me to be to remove algae that's growing on there (which is the main thing that prompts me to wipe down the interior glass of my tank), but is there any OTHER reason you all wipe down the glass? Especially if you're doing water changes every day or every other day, you're not going to get any significant algae growth, so is there another health benefit to the fish of keeping the glass clean that I'm not aware of?


This is a very good question. The short answer is yes, there is another reason for wiping down the glass other than to remove algae. The in-depth answer involves the whole reasoning behind why large water changes and tank maintenance is necessary for healthy discus. It all involves organic compounds that are present in food. Organic compounds are not toxic to the fish, however two undesirable things occur when they are introduced. First, there are pathogens (bacteria, virsus, and parasites) present in every aquarium. These multiply greatly when they feed on the food. Second, the food decomposes and this process produces other compounds that are toxic to the fish. These toxins cause stress on the fish, and that makes them more vulnerable to attack by the pathogens. It's important to know that this is occurring in the tank even if the water appears crystal clean.

When food is placed in the tank it is transported in the water column and adheres to the glass and everything else in the tank. This is where a large portion of the pathogens exist and where decomposition occurs. A good indicator that decomposition is present can be attained by removing something (decor, artificial plants or whatever) from the tank and giving it the "sniff test" by holding it close to your nose. A foul odor indicates the presence of decomposing organic material. Decomposition is a common process in nature as evident by the foul smell of a dead animal or decaying vegetation. I wonder if discus can smell, and how it affects them if they can.

The number one purpose of large water changes and tank maintenance is to reduce the amount of food available to the pathogens (thus limit their number) and to reduce the toxins that result from decomposition (thus reducing stress). A more detailed explanation of this is provided in the following link:


There's more to the story about organic compounds. I have a non-planted show tank with adult discus, and have implemented a filtration system that strips the water column of nearly all of the organic compounds. This is accomplished with the use of a product called Purigen. Purigen absorbs organic compounds, and it is very effective at doing so when used in a reactor. With this I have achieved what I consider very good results. Other than water changes, the only other tank maintenance that I do is done once a month. Uneaten food and feces are automatically removed by the filtration system. Decomposition has been reduced to the point where the tank remains pristine clean without any intervention on my part, other than a monthly cleaning. Algae is completely eliminated and the glass, bottom, and decor remain spotless for an entire month. Bassically what happens is that once the organic compounds are eliminated, the tank stays clean. Here's a link that illustrates the results that have been achieved, along with the method implemented to achieve these results


The above link has several stickies at the top. The results achieved are contained in Parts 2 and 3. The filtration system is explained in Parts 4 and 5. Please be advised that it takes more than just the addition of a Pruigen reactor to achieve the results.

Another thing that the above filtration system permits is to achieve a nice looking bare bottom tank. Some people might not think so, but I like my bare bottom tank so much that I prefer it to a substrate. Here's a link showing the results:


Hope this is helpful for you.

05-04-2017, 08:25 AM
This is a very good point, that is offten overlooked. Most hobbyists think that NH4, NO2 and NO3 are the only factors to determin if water quality is good or not. It happens many times that I am approched for help when fish dies or disease breakout in a tank while it's owner claims that his maintnance is perfect because these three parameters are normal.

Organic loag is not emphasised a lot in the hobby even though it is much important than NO3 for the reasons you have mentioned.

I have been influenced many years ago by your filtration setup and recently built my own system with inspiration from yours. It is composed of an a skimmer that overflows to a barrel after passing over polyster pad for mech. filtration. In the barrel I am using moving bed media similar to K1 (self cleaning) and water is heated. The return flow is split into two, most go direct back to the tank, the rest flows through a denitrification reactor, then Purigen reactor the UV sterilizer all in series.

This was my idea of an ultimate filter that removes solid waste, NO3, organic matter and kills free bacteria and pathogens. This will reduce the need for water changes which is ideal for a wild discus tank.