Beware Killer Sponge Foam!

Last year I picked up at Jo-Ann Fabrics an open cell foam (product name, EZI-Dri by Crest Foam) that looks identical to that used by Hagen and other aquarium supplies manufacturers to make their pre-filter sponges and coarse media... it has the same structure, permeability and color as the Aquaclear sponge and Eheim Pre-filters (that you put over the strainers so food and other coarse solid debris does not get inside your canister).

Upon getting home that day I cut a piece from the sheet to replace my own media and I put it to work.

A couple of hours later the fish had become very skittish and it was evident that it was the material I had introduced to blame for the reaction. I did a big water change after having removed the new material.

Nevertheless, doing initial research, reading the bag and digging up what I could on the internet, the material was supposed to be non toxic and inert in presence of most chemicals.

So I decided to boil it in a strong acid solution and put some of it in a HOB filter on a 55G I have with feeder fish... and a few tetras... this time nothing happened.

I later used the same HOB on my 75G with some discus and peruvian altum and again, the fish showed no reaction. I continued to use the material in my HOB filter (Emperor 400) until some 4 months back. I also used the remaining foam in my 2217's and CSF-4's.

A couple of weeks back I picked up a new bag of EZ Dri (just a little time back I had told Larry and spoke goof the product to him) and I was glad to see the product in a slightly larger, thicker presentation (now it's 22x22x2) and with a new, nice light green color to it. Like when you expose an aquaclear sponge to a weak solution of meth blue.

I noticed the package was esentially the same but it had a little black circle that read "Now with Ultra-Fresh" and in the description I noticed it said something on antifungal properties.

Again going on the internet I found that the Ultra-Fresh treatment consisted of a "built-in" fungicidal/germicidal agent.

I decided to contact the manufacturer directly and told them of my intended use.

The first sentence in the reply from the Sales Manager at Crest Foam was "EZ-Dri WILL KILL FISH". What you need is our T-20 or T-30 foam.

And so, I just wanted to share this with you and warn you, DO NOT BUY EZ-DRI FOAM EVEN IF IT LOOKS IDENTICAL TO THE HAGEN FOAM.

Crest Foam's Regional Sales Manager is supposed to get in touch with me for presentation and pricing on the T-20/T-30 material which is specific por pond/aquarium use. I'm not sure but I think these guys are the actual manufacturers' of the stuff we buy labeled by aquarium companies at several bucks for a few inches of sponge.

I will be posting my follow ups with Crest Foam.

P.D. I already had packed a two inch layer of EZ-Dri in my 2260 which I should be starting up later tonight. Thank God Crest Foam got back to me fast.

God listens. He may not always give you everything you want, when you want it; but he always gives you what you really need, when you need it most!

re: Beware Killer Sponge Foam!

also the poly wadding sold in Walmart; some of the brands have something in it lately.

If you rinse it in a bucket of hot water, lots of milky foam comes out. Some say fire retardant, some say fungicide or something.

check how you mentioned it to Larry , Ed.


re: Beware Killer Sponge Foam!

Hi Dave,

I use Nu-Foam Poly-Fil by Fairfield. I get it at Wal-Mart (same one I also get at JoAnn's). Manufacturer's link:

It's 100% polyester, so it wouldn't need an antifungal agent to resist mildew or mold. Don't know if the words "flame retardant" imply an added chemical or just a quality of the product if compared to polystyrene foams.

In anyway, even if I don't wash mine before use, I am sure people will feel safer if they give it a good rinsing or hot water dip/rinse before using it. I think that by submitting it to a boil we could affect thr product's resiliency, so I wouldn't boil it.

I'll have to stand by this product. It's been in all my filters for the last year and at this point, my fish are probably doing better than ever since I restarted my tanks last summer/spring. Google it up along with keywords "fish", "aquarium", "filters". You'll find aquarium hobbyists are using it all over the U.S., some for many years.

Compare it to Hagen/Fluval or Eheim and you will notice it's a worthwhile buy. Pre-cut slabs run from 6.00 bucks up (17x15x2). At my local Wal-Mart I pay about $8.00 for the 22X22X2 slab, which will render anywhere from 4 to 8 polishing pads (or more) depending on your canister/filter. It looks exactly the same as the Eheim (Fine Particle) polishing pads.

God listens. He may not always give you everything you want, when you want it; but he always gives you what you really need, when you need it most!

re: Beware Killer Sponge Foam!


I hope this serves to clarify things and haven't helped anybody with their own fish kills.

I usually have a chance to catch up with Larry as we e-mail and PM daily and talk over the phone pretty frequently.

Thanks anyways.

God listens. He may not always give you everything you want, when you want it; but he always gives you what you really need, when you need it most!

re: Beware Killer Sponge Foam!

For what it's worth, I only use Azoo Oxygen-Plus BioFilter Sponge filters I buy from DrsFosterSmith. I don't even bother to clean them. I just have a large number of replacement sponges on hand and grab a new one. I use 2 per tank so I always have a viable biological filter in place since I only change one at a time. I use one with a MaxiJet 600 powerhead and the other one in airlift mode. The powerhead draws in so much fine particulates into the foam structure that they are virtually impossible to properly clean. They sometimes undergo a biological action that seems to convert the organics to something akin to petroleum and just have to be tossed.

Once or twice a year I will gather up all the dirty sponges and run them through a couple of times through a heavy duty washing machine at a laundramat. I use warm/ warm and bleach the second cycle. Even these don't hold up long with the powerhead but they do work OK with the airlift side of things. Actually I don't do it myself. I have my house keeper do this. I am allergic to work.

I use the filter model #6. One is supposed to be good for 110 gallons but I use 2 in all 20 to 40 gallon tanks.
Larry Waybright
Trout fly fisherman.

re: Beware Killer Sponge Foam!

In regards to foam I am a car upholsterer and use all kinds of foam everyday. At the supply house they have every kind of foam you can think of available in just about any size/density you want. The warehouse has these huge car sized blocks of foam and they have a mean band saw like thing to cut it with. I am now going to have to consult with the supply house owner about the exact nature of these foams and where he gets the stuff from.

re: Beware Killer Sponge Foam!

Hi Jeff, most any foam that has added chemicals for mold and mildew rejection will be toxic to fish on a higher or lesser degree.
I specifically refer to a type of foam sold under the EZ Dry brand that has a very light off white/green tinge to it. I purchased it as a 23x23 inch square, 2 in. thick. I had used this same manufacturers basic white foam (both are open cell) but decided to write EZ foam and their reply was that this foam WILL KILL FISH!
I bought it at Joann's.

God listens. He may not always give you everything you want, when you want it; but he always gives you what you really need, when you need it most!

re: Beware Killer Sponge Foam!

Most foam that is going to be "general purpose" is treated with some form of cyanide, gluteraldehyde, isothiazalon, or quatenary amonium. Some are added post production and others during process. There are harmful chemicals in almost all plastic reactions, bis2 ethyl hexyl pthlate, di methyl benzine, and iron oxides are used to complete the plastics reaction.
I had an extended e-mail with Larry about the harm of non NSF plastics. Mabey if asked nicely he would post it.

re: Beware Killer Sponge Foam!

We have been testing an open pore or reticulated foam in our fishroom for the last two months. We had two companies send us samples that are the same product we found out. The one we are testing is 30ppi. I have a feeling none of these foams are made in the us but imported. And yes Ed, it is the same stuff sold in pond departments. It's a rigid foam that is very comprable to the one manufactured in Germany. We had the company give us different sizes and have made small filters for 2.5 gallon tanks as well as one that covers the backs of 10 gallons. The one 10 gallon tank had green water and is now crystal clear. It is our plan to convert all of our hydro sponge filters over to this type of filtration. We are working on getting prices for 2" thick pieces cut to fit various size tanks. We also have the option of having them cut to fit the hydro sponges but not sure how that works out as far as cost yet.

If we decide to become a distributor I can have it cut into any size we want. I do belive the more cuts the more expensive so will probably sell in in sheets and let the buyer cut it down to size. The minimum orders are not that overwhelming although buying a bun of foam sure is!

If like the other foam this only needs cleaned once a year as opposed to once a month we will save a ton of time.


re: Beware Killer Sponge Foam!

I talked with my upholstery supplier yesterday regarding this. He is pretty certain that many of his various foams have no sort of fungicide and no flame retardents. He says some special foams have flame retardent stuff in them but he does not carry this stuff. BTW no matter what is in it ALL foam will burn like crazy. Being a reef tank enthusiast I really peaked his interest in the aquarium talk. He has several different foam elements that came with his filtration equipment and he is bringing them to work so that we can compare them with the foam he has in stock so I will find out soon whether or not I have a massive supply of foam for sponge filters. His business has a website and ships all over the USA.

Here is the link to the foam part of the catalog to give you an idea of price. Soon enough I will know if it can be used for aquaria...

re: Beware Killer Sponge Foam!

Thank you for educating me Bev...I didn't know a thing about reticulated or open cell or closed cell or any of that. And you are probably right I don't recall seeing any foam that looks like the reticulated open cell stuff in my supplier's warehouse. I am going to see exactly what is there however because I know many of the foams we use are at least open celled and some of the dacron layering stuff seems to be articulated if you will although dacron is not the same as foam I think.

I like the idea of a two filter system where you just throw one away and put a new one on periodically instead of cleaning and reusing. I know...very wasteful...but I am very lazy unfortunately. :)

re: Beware Killer Sponge Foam!

Saving on sponge cleaning is why one of the reasons we have been looking into this. We could not afford to do 170 tanks on the high priced foam from Germany so were looking for an alternative. Disposable is, for us, too expensive in the long term. Plus we can put this in front of the pipes that run into each tank for draining and filling so fish cannot hide behind the pipes and be a royal pain to catch.

There are two sizes of the open cell 30ppi and 15ppi if that helps you in your search.