![]() Aquarium Cleaning; Reasons and Methods for Water Changes.This article will help you maintain a healthy tank via optimum cleanings, resulting in an Aquarium that is a compliment to your Home/Office.
Search AAP Supplies or Information By Carl Strohmeyer-PAMR 45+ years experience Updated 2/24/21 REASONS FOR WATER CHANGES (Freshwater OR marine):The Reasons "WHY" are the MOST important aspects of why we clean and change our aquariums water. It is also worth noting that most of these “Reasons for Water Changes” are inter related, so addressing one reason often has an affect on another; the results can be ignoring one "reason" often has a domino affect on other reasons". (1)* Nitrate control- A nitrate level of 15-20 ppm or less is best for saltwater fish (10 ppm or less for Reef), 40-50 ppm or less for Freshwater fish. With a Planted Freshwater aquarium, a Nitrate level of at least 15 ppm is better, as plants need some bio available nitrates in the water column. Please note for marine aquarists; an average protein skimmer often cannot keep up with the organic waste output of an average stocked marine aquarium, although many modern Marine Protein Skimmers do a much better job than they did as recently as the 1990s especially when coupled to a good Ozonizer. It is also noteworthy with marine aquariums, utilizing other methods for nitrate control other than just water changes is important since the cost of a quality marine salt can get quite expensive if large percentage water changes are needed. Product Resources: I often have told my clients/customers that Nitrate removal was an important reason for water changes, and utilizing vacuuming as a method of removing organic mulm is an effective way of maintaining low nitrates (especially in the absence of nitrogen reducing anaerobic filter bed). See Reference Note. In freshwater aquariums (especially in the absence of a large amount of thriving plants), water changes using a gravel vacuum to remove ALL the organic mulm before it goes through the full nitrifying part of the nitrogen cycle plays a major part of controlling nitrates in a freshwater aquarium. Test: Whatever number that exceeds what you establish as maximum nitrates such as 40 ppm may indicate a water change is needed. Please read these articles for more about Nitrates & related information: (2)*GH and Electrolytes, positive mineral ions; this is related to the above point. This is an important reason that is often missed in determining whether or not adequate methods, frequency, etc. of water changes are being utilized. If your aquarium mineral ions/electrolytes are low, you are likely in need of a water change using water high in electrolytes/mineral Cations and/or should be employing products such as Wonder Shells, Aragamight, SeaChem Replenish and possibly aragonite.
The picture to the right clearly demonstrates how even a 50% water change using Prime too does not completely remove the oxidizer added for this test (Potassium Permanganate) compared to the tank utilizing an AAP Wonder Shell. References: It should be noted that aragonite often will not respond rapidly enough to lower mineral levels as compared to Wonder Shells, Seachem Replenish or Equilibrium, or simple water changes with water rich in mineral cations (positive mineral ions/electrolytes). Product References: Test: a GH test is likely not going to be accurate for a water change as most residual minerals remain even when tests remain within desired parameters. That said any lower number of desired GH such as 150 ppm indicates either a need of more GH additives and/or a water change.
Test: Unlike GH, carbonate buffers (KH) are often quickly depleted and any lower number under the desired KH target such as 100 ppm indicates the need for a water change and/or addition of buffers. (4)*Lowering of DOC & Removal of Organic Mulm (Sludge); DOC stands for Dissolved Organic Compounds (some refer to the ‘C’ in this abbreviation as Carbon which would relate to carbon based molecules). This is achieved two ways in cleanings: * The second aspect is surprisingly misunderstood, even by experienced aquarists and that is by thorough vacuuming of organic mulm, you remove a major cause/source of DOC. Another device, the electric (battery powered) “Bag” vacuums are not nearly as efficient as Diatom Filters. These use a bag that does not even trap 25% of the DOC causing mulm that a true micron filter can do. My tests measuring Nitrates, KH, & Redox show this.
Test: Similar test to Nitrates, so besides visual indicators; high amounts of DOC & mulm will generally be indicated in rising nitrates, unstable pH, and dropping KH. (5)*Removal of harmful elements; There are many toxins that can be introduced, airborne or in other ways enter the aquarium that are not easily measured. Test: No 100% applicable test, although yellowing of the water, followed by clarity after using these products may be a partial indicator. (6)*Control of Bio Load; Although an aquarium cleaning/water change is not the long term answer to an over crowded, over fed, and under filtered aquarium; cleanings are certainly necessary to lower your bio load by removal of decaying organics in your gravel, under décor, and often in under maintained filters as well.
So here's the summary of "How to "Test"
For further information, please read: *Aquarium Redox Balance *The use of UV Sterilization for Aquarium Redox ... this is a MUST read with the plethora of junk UV Sterilizers now flooding the market that are in reality only water clarifiers, not true UV Sterilizers!
Test: Again, similar test to Nitrates (& pH/KH), so besides visual indicators; high amounts of wastes (such as fecal matters) will generally be indicated in rising nitrates, unstable pH, and dropping KH. (9)* Control of algae growth; this aspect is often missed, yet is very basic. Water changes (assuming replacement with water that has natural balanced nutrients) will generally return the proper balances of Macro nutrients (PO4, NO3, K) to a freshwater tank for plants to out compete algae. In saltwater excess nutrients are removed, again allowing for less algae growth. Test: No applicable test other than noticeable less algae growth (10)* Rinsing of bio-sponges, media, etc. in used aquarium or de-chlorinated tap water (generally not straight tap water). This includes sponge filters, bio balls, and ceramic media in canister filters (canister filters need to be cleaned more often than many aquarists think due to nitrate producing and KH reducing mulm buildup). (11)* Disease eradication; changing water for disease eradication may not solve the problem, but may be a step towards the problem when done in conjunction with medications/treatments (even bleachings and subsequent aquarium re-starts). Since this is not really the scope (purpose) of this article, please see this article where I give some water change examples for disease/parasite problems: I will also note that water changes are important prior to each treatment with aquatic medications so as to lower medication absorbing DOC and “spent” medications themselves so as to render more effective treatments. As well, changing water, especially using a gravel vacuum to go through gravel lowers many pathogens in the aquarium, even including Ich trophonts. Test: No applicable test, although small water changes after EVERY treatment and a larger water change after finishing treatment is strongly recommended so as to lower medication absorbing compounds in the water column. * All these reasons are based on 30+ years of professional aquarium maintenance with some of the largest accounts in Los Angeles, CA Summary of "Reasons for Water Changes;" HOWEVER, if your aquarium requires 100% water changes every week to maintain stable pH, nitrate, ammonia, etc; My experience with such aquariums has shown these problems:
Back To Top Original Internet Publish Date: 2005 ![]() Remember, it is your purchases here (both small & large) that keeps these world class information articles free. Purchasing elsewhere such as Amazon will only result in this free information going away someday!! RECOMMENDED READING For those looking for ACCURATE information about stepping up to a higher level of fish care, this article is a MUST READ: ![]() Ultraviolet Sterilizer Use; Facts & Information The most RESEARCHED, & IN-DEPTH article on the subject of UV Sterilizer, Clarifier Use in Aquariums or Ponds ANYWHERE. Based on over 34 years professional use too!! RECOMMENDED PRODUCTS ![]() ![]() The latest technology for pure water production from Europe's leader in aquarium/pond equipment ![]() ATI Hydro Sponge Aquarium Filters for bio and mechanical aquarium filtration. New Hydrosponge Pro filter for high bio load tanks. Also replacement sponges and parts for Hydro Sponge ![]() The SunSun HBL-501 & 702 combines Dual (701) cartridges AND Dual (702) Bio Sponges for reliability and a price that beats many filters of half the capacity and double the price ![]() Professional Grade Aquarium Silicone ![]() There is NO Better UV for your aquarium; Maximum dwell time and performance that will improve all fish disease resistance unlike most now sold which are little more than water clarification devices!!! For Replacement UV Bulbs to keep your aquarium clear in between Water Changes: ![]() Page 1, (Compact H Series) UV Replacement Bulbs |
FREQUENCY (& volume of water change);Use these factors to determine frequency (& possibly volume/size).
*After proper feeding, filtration (including choice of filter media) good cleaning routines, as a starting point; 10-20% water changes with a gravel vacuum once per 2 weeks is suggested. *Caution should be used with larger volume water changes (especially over 50%) so as to not cause pH spikes either up or down, as well dramatic changes in other parameters as well. AQUARIUM CLEANING BASICS:For an established, healthy aquarium I generally recommend changing 10-20% of your aquarium water once per week (best) or at least 25%+ once per month. With good filtration and plants (live rock in marine aquaria), you often can go longer than once per week. Product Resources: *Start Right Water Conditioner *SeaChem Prime Please note: Contrary to some information thrown around without much research, vacuuming the layers of gravel that contain aerobic (nitrifying) bacteria will NOT destroy the bacterial colonies, as research (that really is not that new) has shown these bacteria to secrete a glue like substance to the media they cling to and a gravel vacuum will NOT dislodge these bacteria. See this article about the aquarium nitrogen cycle: NITROGEN CYCLE AND AQUARIUM CYCLING; How the Aquarium Nitrogen Cycle Works STEPS:
For more about methods of water change and procedures to refill your aquarium, please read further in this article under procedure. METHODS FOR WATER CHANGE:For cleaning your aquarium (freshwater or saltwater) a Gravel Vacuum attached to a siphon or re-circulating filter works best. These vacuums are quite easy to use; simply push the bell of the vacuum into the gravel and quickly back out. If you are having problems with sucking gravel into the siphon hose, try kinking the hose with your other hand to slow the out flow to keep gravel from being sucked up. Make sure and lift ornaments out of the way and vacuum in as many dead spots as possible. It is important to get as much of this organic “mulm” out of the aquarium as possible as this is what leads to higher nitrates, ph crashes (due to nitric acid production during decay), and resulting in poor KH levels. As a generalization based on my decades of professional aquarium cleaning over literally 1000s of aquariums, the proper use of an aquarium vacuum that includes vacuuming under ornaments and rocks as well as rinsing and/or changing of dirty filter media with smaller 25% water changes (or less) will make more difference than large water changes. Product Resource: *Lees Aquarium Gravel Vacuum
At the most if the substrate is unusually dirty or you would prefer a new gravel/substrate for aesthetic reasons, I recommend removing at most 1/3 of the gravel at 3-4 week intervals. As noted earlier, if organic mulm build up is so-bad, you may need to add water while changing it to get the aquarium to a reasonably clean state. Make sure that water coming in though is temperature & ph adjusted. Starting the Gravel Vacuum is usually quite simple (depending upon the brand though). With the Lees, simply placing the end of the hose (water exhaust) into a bucket, the turning the “bell” of the vacuum into the tank and rotating it to remove air, then moving the vacuum bell up & down with quick actions will allow the quick start valve to start the siphon. Tips to starting a basic gravel vacuum:
Further Siphon Tips (including attached to hose):
DIY Gravel Vacuum System (Python Style)
BOWLS OR SIMILAR:
PLANTED AQUARIUM: REEF: GERMAN METHOD: FLOW THROUGH METHOD Combined Methods PROCEDURE and REFILL (Continued):You can drain this water into a bucket or attach the siphon to a long hose and drain it outside or into a toilet using gravity. Product Resource: Lees Vacuum Kit I prefer to leave the fish in during this process even if the aquarium is quite dirty, as I have found that more stress is added to the fish removing them and then placing the fish back in new water conditions that the fish are not accustomed to. Only in extreme circumstances did I remove the fish (even then, my results were better with a "flow through" cleaning method while leaving fish in) Although in the Marine aquariums I maintained, I brought my own water and it was invariably colder than the aquarium, but this does not present as much of a problem as many think. If you do some math; Say your aquarium is 78 F and you add 20% water back that is 68 F, that is 1/5th the volume, so 1/5th of a 10 F difference is only 2 F. If hot water is needed, this is best added to a bucket of non heated water from whatever source so as to not accidentally scald/burn fish pouring directly into the aquarium. As well make sure your new water does not adjust the pH more than .2 on the logarithmic pH scale. Do not add RO (Reverse Osmosis) water directly (other than topping off for evaporation) until water is re-mineralized and buffered correctly. That said I respectfully do not agree with this for the reasons that the use of many conditioners such as AAP Res-Q or Seachem Prime also help add electrolytes and balance Redox (albeit temporarily) which allows for less oxidative stress on the fish and further aids in the water quality improvement a water change provides. Please see this article for more about Chloramines: *What is more important is adding a de-chlorinator to your tap water (if tap water is used) WHILE the water is being added if you are filling via a hose, DIY Python, or similar device. I prefer to use the full strength of the water conditioner as per aquarium size so as to obtain all the benefits of reducers, electrolytes, etc. of your water conditioner. *If using a bucket, I add the water conditioner per each bucket prior to adding each bucket back to the aquarium. I also recommend adding further water conditioner as per the complete tank volume after bucket(s) are added to obtain all the benefits of the particular water conditioner used. In healthy, well established aquariums, I often use AAP Shieldex or AAP Res-Q. Please see this article: Aquarium and Pond Answers; Water Conditioners Review. Prime or Amquel Plus is a must for tanks with ammonia or nitrite problems. *AAP Res-Q *AAP Shieldex *SeaChem Prime Back To Top Cleaning Machines/ Diatoms
Vortex Diatoms; although not commonly used still can have their place for cleaning established aquariums with high bio loads, however with the advent of the aquarium cleaning machine which performs similar functions WITHOUT the need to stir up the tank as much and add stress to the fish by doing so, these have pretty much gone the way of the dinosaurs IMO. Sludge Remover Vacuums; these devices are not as powerful or as efficient as a Vortex Diatom, however these do not stir up the water (which can stress fish) as much as a Diatom Cleaning Filter. Reference Note; Part of this article written in 2005 was used without citation in a forum here: http://www.arosg.com/f153/nitrate-control-fw-sw-aquariums-6853/ What is noteworthy is that this forum post is much more recent, 2013. More interestingly it is only Google and their spammy algorithm that even brings up this non cited forum post. Other search engines such as DuckDuckGo, Yahoo, Bing do not show this forum since it did not cite their source. In fact the other search engines note my blog post that I copied from my article in 2006. What is sad is a very disrespectful forum (nano-reef.com) attacked me for plagiarizing my own content!. A little homework and commons sense would have shown that the content in question was my own and being used by others without permission or at least proper citation. FURTHER READING: How To Clean A Fish Tank Like A Pro: 6 Aquarium Cleaning Methods For Optimal Tank Health VIDEO:Here is my NEW basic Aquarium Vacuum/Siphon cleaning demonstration that I made a video for (with some added help this time). I hope this is better about demonstrating vacuuming basics (making videos is not a talent of mine). If you have found this site helpful (or the sister site Aquarium and Pond Answers), please consider a donation to help with the 100s of hours of research and regular updates that go into these articles: For our business partner webpage: Business Partners; Great Links | Basic_Aquarium_Principles | Basic_Saltwater | Aquarium_Disease | Aquarium_Lighting | Goldfish_disease | Aquarium_cleaning | Nitrogen_Cycle | Redox_Potential | Clear-Pond | Aquarium_Filtration | Aquarium_Medication | Aquarium UV Sterilization | Vibrio_Aeromonas | Aquarium_Ich | Columnaris | Aquarium-KH | sponge_filtration | Aquarium-Plants | Quality_Fish_Food | Oodinium | | Return Home | Aquarium_Information | Aquarium Products | Downloads | FAQ | Contact Us | View Cart | Other | |
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