(Read my review of the Zoo Med 501 turtle filter with fish and shrimp.)

I’ve been using the Zoo Med 501 turtle filter for several months now and here’s what I think about it:

Overall: a good ‘first’ filter for small pet turtle habitats. The turtle filter will eventually need to be replaced with a stronger, bigger filter when the turtles grow and the turtle tank is upgraded to a larger size.

The Turtle Filter review

Strength: Rated for up to 30 gallons of water with a max flow rate of 79 gph (gallons per hour). The max flowrate is the rate that water is pumped through the filter without any filter media. The circulation rate would be the rate with the filter media actually installed. It’s typically about 80% of gph, so flow rate would be roughly 63 gph (79 x 80%). This means that for 30 gallons of water, it will circulate all the water just twice (63/30 = 2.1). Not bad…but for turtles circulating all the water 3 times or 4 times would be more preferable, but twice isn’t bad.

Filter media: The turtle filter comes with all the media you need and is ready to use right out of the box. It comes with a sponge (mechanical media), a carbon bag (chemical media), and ceramic rings (biological media). Carbon isn’t really needed in a turtle tank, but if you really wanted to continue using it, it would be cheaper to buy your own carbon than to keep buying the Zoo Med branded carbon packs. I prefer to ditch the carbon and just use more biological and mechanical filter media instead.

Zoo Med 501 Turtle Canister Filter

Noise: It’s a quiet turtle filter. You’ll hear it running if you’re right next to it, otherwise you won’t hear it at all. The waterfall sounds from the spraybar can be avoided by putting it underwater or by aiming the water to spray right on the wall of the pet turtle aquarium.

Complaints: My main gripe with the turtle filter is that you don’t have much flexibility with how to arrange the media. The canister is divided into two parts, one for the biological and chemical media and the other for the sponge with the water flowing only in that direction. Because of the design, you can’t adequately have the water flow through the sponge first (which makes the most sense) then through the other media next. Because the water will flow through the carbon or rings first, the turtle filter will clog a lot quicker than it otherwise would.

By the way: there is no right/wrong order in inserting the carbon and ceramic rings. They each filter out different things from the water and it doesn’t really matter which one cleans the water first. In the case of this filter though, it would be better to keep the carbon on the bottom and the rings on top. Doing it the other way around will only make this turtle filter clog quicker.

My Experience with this Turtle Filter

I’ve used this turtle filter for two red ear slider turtles for when they were hatchlings to about 2.5" in a 5.5 gallon tank starting with 1 gallon of water which slowly increased to 4 gallons of water. It has done an excellent job. It isn’t strong enough to suck most of the debris out of the water, but it keeps the water looking clear and clean. Spot siphoning everyday or so is needed to keep the tank looking clean. The spray bar does a passable job of providing surface water agitation in a small aquarium but isn’t enough to remove the oil film that forms on top of the tank water. All the ammonia and nitrites are completely removed from the water with the filter, but with two pet turtles a weekly 100% water change was needed, as nitrates only took a week to get to 40ppm. The turtle filter can get clogged fairly easily, so I usually clean the filter media every time a water change is done. Also, the filter tubes accumulate algae and dirt fairly quickly. It is very easy to prime (start), and will even start even if the canister isn’t completely filled with water.

I will continue using this filter in the small tank long after my pet turtles have been moved to a much larger tank. It did a good job with my red ear slider turtles and I’m positive it will do an excellent job with fish and shrimp, which generate less waste. Read my review of the turtle filter used with fish and shrimp.

Get the Zoo Med 501 Turtle filter.


  1. My zoomed501 is very noisy ! ? I’ve used the rubber plugs in the bottom and filled it up completely with water, but it still makes a rather loud high pitched noise. I can’t discover what could be wrong ? It seems to pump alright though. ?? Do you know what might be wrong or what I can check ?



    1. does the 501 filter have any air left in it? It’s possible the sound is the filter removing air from the canister. If that’s the case, leave it running and it will get quiet as soon as all the air has been removed.

  2. Hi Forlogos,

    Thanks for your reply. I refilled the pump twice. The last time I also took out the white rotor (i think it’s called) and after putting it back it already made much less noice when running it. Now it runs very silent ! Appearantly it wasn’t fitted right and made a resonating, mechanical noise.

    Thanks again.


Leave a Reply

Your email address will not be published. Required fields are marked *