Filter For Fish Tanks

Filter for Fish Tanks

Filtration is very crucial and its importance cannot be brushed off in any fish tank or aquarium. The fact of the matter is that the higher the level filtration in the fish tank the better it is for the fish. Discus fish require one of the highest levels filtration because of their messy nature. It is recommended that you always have a level of filtration which is way higher than the size of your fish tank. This clearly means that if your fish tank is say 50 gals, then your need a larger filter of up to 100 gals or even more or chooses to have more than one filter of 50 gals. Here we will discus the best filter for fish tanks.

The best filter for fish tanks come in a variety of types, namely; under-gravel (UG), hang on the back (HOB), internal and canister. The most preferred Discus fish filters are mainly internal and HOB (hang on back) filters even though canister filters are also preferred for larger fish tanks. The main reason why internal and HOB filters are preferred for Discus fish is because Discus fish are very messy when they eat. This means their rate of making the water in the tank dirty is way higher compared to some other species. The reason attributed to Discus fish messiness is their feeding habits as well as their straight intestinal tract. This means therefore that the filtration system should in this case have a higher rate of filtration than in a normal condition. This is what internal and HOD filters do exactly. The rule of thumb for filtration is 10x per hour per tank turnover. This allows good water movement, but of course is the bare minimum when it comes to Discus fish tank.

Apart from the effectiveness of a filter in doing the filtration, its price is also paramount. When you choose the best filters for discus fish you must compare both efficiency and the price. Also, the noise levels of the filters are considered. Aqua clear which is HOB filter is among one of the very quiet ones. Do not use an under gravel filter in a discus tank. Under gravel filters are intended to trap the waste under the gravel. Eventually the waste will become bacteria and foul your water. Under gravel filters are fine for other fish but not for discus.

Most of the varieties of filters above come complete with filter media which is actually what goes inside the filter. The filter media can be ceramic rings, sponges, pads, etc. however, some of the filters also come with charcoal. The importance of charcoal in the fish tank is debatable and is mainly used to remove medications from the water after treating for an illness but generally but aside from that, charcoal isn’t really necessary in the discus fish tank. This does not mean however that charcoal can be harmful when kept in the fish tank filter but you may choose to replace the carbon (which is the component of charcoal) with another form of filter insert such as a sponge or ceramic rings.

The filter should be cleaned every 6 months. When cleaning your filter only replace the sponge/cotton material and do not rinse out or change any of the other media in the filter. It very important that the beneficial bacteria in your filter is not disturbed. Therefore, it is recommended that you only replace the filter cotton/sponge media when it is critically necessary.

Here is my list of the best filter for fish tanks:

Canister Filters:
1. Hydor Canister Filters
2. Fluval FX series
3. Fluval canister filters
4. Eheim canister filters

HOB Filters:
1. Marineland Penguin Series
2. Aqua Clear
3. Whisper

Sponge Filters (primarily used for discus breeding):
1. Deep Blue Sponge Series
2. Hydor Series

In conclusion, when choosing the best filter for Discus fish, look for the one with the highest filtration rate. Discus fish are not cheap fish so you want to ensure that you have the proper filtration to maintain healthy fish.

Back to Discus Fish For Sale Home


  • Dan Evangelho
    Posted September 8, 2017 1:14 am 0Likes

    Wow, I’ve been under some serious misconceptions for years, I guess!! Is the following not true? “The reason to use carbon is that it removes dissolved organic compound from the water. This has been shown experimentally. Removing the dissolved organics will increase the effectiveness of the biological filter.” (Dr. Tim’s Aquatics) And I’ve always used an undergravel filter in conjuction with other filters believing that it helps to isolate the detritus away from the fish and becomes an additional bio filter.Even tho my experience in the hobby goes back to the 70’s, I know a lot has changed. I’ve had discus for less than 2 years now, with mixed success – first was a poor source (most died eventually) but I still suspect slow growth. If you have the time I’d appreciate your critique of my Discus tank. (I ordered from you a few months ago). I have a 100 gal tank with 10 mostly-juvenile discus, 2 mature angels (no problems), 4 3″ Clown loaches, 3 4″ Red-tail Loaches and a 3″ Raphael cat. Ammonia and nitrite are always zero with nitrate generally below 5-10ppm. Filtration: A PennPlax 1500 Canister; the intake comes from one of the 5 uplift tubes of the undergravel filter, returns by spray bar. The two end uplift tubes have power heads aimed at each other to counter eny extreme flow through the tank. There is also a Magnum 350 (old school) HOB filter whose return flow joins with one of the power heads. I use 2 300W submersible heaters to maintain a fairly constant 84 degrees. A 50% water change (30% RO water) with an average TDS of 150, brought to matching temp, is performed every three days. The tank is not planted, but decorated with artificial plants, lava rock and the like. Whew! Well, Rob, any suggestions for improvement???? Thanks! Dan

    • discusguy
      Posted September 8, 2017 8:46 am 0Likes

      Hi Dan,
      Thanks for the comment. Regarding your aquarium setup it sounds like you have a fairly solid setup. With regards to your under gravel filter, as long as the waste from the filter is siphoned up and out of the tank then its fine. If the waste from the under gravel just sits in the under gravel filter and never comes out of the tank it will create a lot of bacteria resulting in the need for more water changes. Is that why you do 50% water change every 3 days? That’s a lot of water to be changing every 3 days in such a large tank if you ask me. However, if you don’t mind doing it that often then more power to you! The more water changes you do the faster the discus will grow! My personal show tank is 110 gal and I do one 50% water change every 2 weeks!

  • Bill Lewis
    Posted September 23, 2017 12:15 am 0Likes

    Interested in Discus, have raised and bred angel fish for several years. I am interested in 6 Discus. Thank you for all the information and great article.

add your comment