Kitty litter substrate

After many failed attempts at growing plants in sand, I had eventually succeeded with a few species in a tank that had a good year's accumulation of mulm stirred into the substrate. I had a very good light on the tank - a Catalina 4 bulb T5 high-output fixture with individual reflectors - and eventually concluded that substrate nutrients were the limiting factor. After I moved and was able to bring at least some of each plant species I had (described here), I decided to try to fix the underlying problem. Every fish I've had has seemed happier in a tank with plants, and the plants are fun to grow too. Erica suggested kitty litter as a substrate (on page 25 of that thread). I had initially intended to lay down a layer of topsoil and cover it over with litter, but after reading a chemical analysis she posted of the stuff I was convinced that the soil was unnecessary.

I used WalMart brand Special Kitty litter, it being the only one I was sure didn't contain leachable chemical additives. Labels on any of the available brands were not helpful in determining their contents, but all of them made some sort of claim like "odor neutralizer" or something that suggested an additive.

The tank was set up somewhat hastily because the air pump that was powering the sponge filter in the moving bucket had failed two days before the tank was delivered and I was in a hurry both to address aggression due to overcrowding and underfeeding and to alleviate the rapidly deteriorating water conditions. The bucket was overstocked to the point that twice daily 90% water changes were not keeping it from smelling bad (though they did seem to stress the fish). I ended up just dumping in a 25 pound bag of kitty litter and pouring water on top of it unrinsed. This is definitely not the recommended procedure, but due to the chaos of moving I didn't have a second bucket to rinse with. In retrospect it might have even been better to fill the tank with water, add the fish, and use that bucket to rinse the substrate. I didn't do that because I wasn't sure if the litter was fired or not, and thought it might soften in water and muddy up even if rinsed. It turns out the particles hold together pretty well and that probably would have been fine.

Pouring water over unrinsed litter resulted in extreme turbidity with only about an inch of visibility. I ended up not adding the fish for another 18 hours while I ran two large sponge filters with air pumps and an Aqueon 55 hang-on-back filter to try to clear the sediment. After two days the water was reasonably clear but I still thought a large water change would be needed to remove the remaining silt. At this point I removed one sponge filter, leaving the cycled one that had traveled with the fish, and rinsed out the other in tank water. Both produced a huge amount of silt when squeezed. The HOB filter pads were essentially clean. It does not appear to have made any significant contribution to the cleanup. Unfortunately I have no pictures of the tank during this period as it just wasn't a priority. At this time I added the plants that traveled with me.

By the third day the water was crystal clear and has remained that way. Moving plants still stirs up a small cloud of silt, but it settles quickly. After two weeks I replaced the air pump on the sponge filter with a 160 gph powerhead and removed the HOB filter because even with an excessively high water level it was causing too much downward current underneath it which was both stirring up the substrate and splashing the light fixture. One thing I noticed in the move was that the light's reflectors had developed hard water deposits that were probably diminishing its performance. After trying to clean these, and replacing the bulbs, I could see a marked improvement in the color and brightness of the light. The powerhead was significantly larger than I had intended, but was the smallest available at the pet store. The hardware store I checked had some smaller capacity pumps but they all had intake screens on both sides of the housing rather than a pipe, so they weren't suitable to power a sponge filter.

Here's a series of pictures of the tank today, arranged from left to right:


On the left are some miniature amazon swords (purchased) and some Ceratophyllum demersum collected in SC. The hornwort is entwined in a plastic plant of similar appearance to anchor it to the substrate. On the right side of the first picture are some Rotalla and an unidentified aquatic grass also collected in SC. The second picture shows the middle of the tank with the sponge filter and powerhead partially hidden behind a stand of hornwort and flanked by a pair of amazon swords. Behind the sword on the left and barely visible is a banana plant, also from SC. The right side of the tank has just one Anubias on a piece of driftwood and some silk plants. This area of the tank receives heavy flow from the powerhead which makes it difficult to keep plants anchored there. The shiners seem to appreciate the current sometimes though. The Val survived the trip but not the replanting. I had some pieces of water lettuce too (this and the Val also collected in SC) but only the smallest sprig survived the trip. I'm interested to see whether it makes it. This had been by far the dominant plant in the tank before the move due to its ability to access atmospheric CO2.

The tank currently houses four bluespotted sunfish, one American eel, three shiners, one swamp darter, one Gambusia and three golden topminnows. I might like to add more darters later, but unless I can bring the temperature down that isn't going to happen. The tank has 216 watts of light shining on it, which is keeping the temperature high. All the plants are pearling and streaming little oxygen bubbles. Unfortunately so are several species of algae, so I may be able to cut down on the light some.

Further photos will follow as I hopefully get the algae under control.

Congrats on your new setup! Hopefully it will create a nice, lush environment. I agree that sand is a terrible substrate for native plants - the particles just don't hold enough nutrients on their surfaces for the plant roots to get.

Hopefully the algae problem will get resolved soon. Cat litter is just like any other non-gravel substrate - it's nutrient content depends on where it was mined. Even within a single brand, it is often mined in different places. It is possible to have cat litter contribute to high phosphorus loads.

Since you have Ceratophyllum in your tank, I would NOT recommend using peroxide for algae control. It seems to melt that particular species. I have not had that problem with any other species, but there are probably a few others that are sensitive as well.

Let us know how the tank progresses!

It's particularly harmful to Valisneria also. I always found more efficient ways of killing vals, but I did some searching on the topic and found a study that quantified damage to different vascular plants from peroxide algae control. Val was just about even with Ceratophyllum.

Thanks for the tip. I was thinking I might still try a small amount with the pump turned off though, more out of curiosity than for algae control. I think peroxide decomposes fast enough that it might not make it far in the tank.

It's particularly harmful to Valisneria also. I always found more efficient ways of killing vals, but I did some searching on the topic and found a study that quantified damage to different vascular plants from peroxide algae control. Val was just about even with Ceratophyllum.

Do you remember where you saw it? I'd like to read what she found.

A little clarification on the val and peroxide... Peroxide melts val (V. americana) and particularly giant val (gigantea)in SOFT water. I've had no problem with using them together in my neutral and harder water systems. As for the true mechanism, I have no tested explaination, but my guess is that it has to do with calcium uptake/preference by the plant or a chemical reaction (the peroxide is less volatile with additional calcium) or both.

Todd

Edited by farmertodd, 07 June 2011 - 12:05 PM.

Here.

I'm not sure this matters at all, but I find it interesting that more than two weeks after filling the tank there are still large pockets of air trapped under the litter which are periodically disturbed by the eel or a crayfish digging, or by me planting something.

Since I don't have anything breaking up the surface, a film of organic matter has formed. This is trapping the oxygen bubbles. By morning these have mostly popped or dissolved, but here's a picture of the surface in late afternoon:

I'm not sure this matters at all, but I find it interesting that more than two weeks after filling the tank there are still large pockets of air trapped under the litter which are periodically disturbed by the eel or a crayfish digging, or by me planting something.

My kitty litter kept those pockets of air for months and months. They're fairly stable.

Pouring water over unrinsed litter resulted in extreme turbidity with only about an inch of visibility.

Ah, oops. I probably should have warned you about this. And no, Special Kitty does not get better with rinsing. I tried rinsing it myself, unfortunately, for many hours before finally figuring out that all I was doing by rinsing it was getting less and less of it after each rinse. The big particles break down too much to make rinsing worthwhile. Instead what I do is to pour the water very carefully and slowly when initially adding it to the tank. It's worthwhile to put a bucket in the tank and to pour the water into that to avoid kicking up the substrate. And then, once the tank is completely filled, I use synthetic sea sponges in the filter (link: http://www.walmart.c...e-1-ct/10322263 ) to capture small dust particles. The sponge that I linked to above, the $3-5 Walmart synthetic sea sponge, is wonderful. It captures so many dust particles that it turns black. Then you lift it up out of the filter (carefully! With a bucket under it) and squeeze it out and the water coming out of it rinses black for a good solid five minutes. It makes the water in the aquarium crystal clear within 12 hours. I tested it this last time I moved, three or so weeks ago, and had one tank running with the sea sponge filtration and one with absolutely no current. The sea sponge tank was crystal clear before I went to bed that night and the untouched no-current tank was still foggy.

Since I don't have anything breaking up the surface, a film of organic matter has formed. This is trapping the oxygen bubbles. By morning these have mostly popped or dissolved, but here's a picture of the surface in late afternoon...

Yeah, my tank got a slight film on top as well after it was first set up. It wasn't extreme enough to trap bubbles, but I could see the slightly oily looking reflection on the surface of the water. I just got up and checked the tank, and it's gone now. I have a lot of surface agitation and many different absorbing layers in my filter, so that's probably why it disappeared.

Edited by EricaWieser, 07 June 2011 - 09:22 PM.

How large is this tank? A 4 bulb T5 HO fixture seems like an awful lot of light, especially if it's not suspended above the tank. If it's unheated (except for the light) and you're not adding CO2 or fertilizers, you're going to grow lots and lots of algae unless the tank is a lot bigger than I'm thinking.

Is there any way you can adjust your powerhead's outlet to agitate the surface of the water? It'll help a lot with your scum and get more CO2 into the water (unless you're adding it already.)

In any case, good luck with your tank!

It's a 55 gallon. The light is keeping it plenty warm. My thermometer is MIA in the move, but the water is warm to the touch, so certainly warmer than I really want it.

... increased filamentous algae growth on plants damaged by H2O2 ...

Here.

... increased filamentous algae growth on plants damaged by H2O2 ...

The article is about controlling noxious aquatic weeds (and algae) using peroxide - the intent WAS to kill/damage the plants. It's been a long, long time since I took chemistry, but the concentrations that were used in the study seem very high to me. They used 1 and 2 mM solutions of hydrogen peroxide. When treating algae in tanks, I typically use 1 oz per 10 gallons of 3% peroxide.

I can't really do the math to compare these concentrations. Maybe Erica can help.

Here is a great quick filter and you can get it down to 5 microns if you want.

http://www.cichlid-f...&highlight=kiss

i have used it many times to clear a cloudy tank.

The article is about controlling noxious aquatic weeds (and algae) using peroxide - the intent WAS to kill/damage the plants. It's been a long, long time since I took chemistry, but the concentrations that were used in the study seem very high to me. They used 1 and 2 mM solutions of hydrogen peroxide. When treating algae in tanks, I typically use 1 oz per 10 gallons of 3% peroxide.

I can't really do the math to compare these concentrations. Maybe Erica can help.

You used a solution of 0.69 mMol concentration, which is less than the solution of 1 and 2 mMol used in the paper. However, the difference between your concentration and the concentration used in the paper is only 0.3 mMol, making the two values fairly close.

Math:
From website http://answers.yahoo...03214038AAGDreQ , 3% hydrogen peroxide = 0.88 moles/Liter
(0.88 mol / Liter ) * ( 0.0296 Liters / 1 US fluid ounce used ) = 0.0261 moles of hydrogen peroxide added to the tank
10 gallons = 37.85 Liters
0.0261 moles / 37.85 Liters = 0.000689 Molar hydrogen peroxide

I will say it's effective against algae in far smaller doses that that. The last time I used it, I took an eyedropper and squirted a small amount of undiluted 3% solution on the problem areas. Not much contact time was required at that concentration to kill the algae, but it quickly diluted in the tank volume, not even harming algae a few inches away. It takes longer to treat that way obviously, but I may test it with most of the Ceratophyllum removed from the tank to see if it's safe.

You can spot treat algae to kill it (peroxide or excel are commonly used) but it'll just grow back unless you figure out what is causing it to grow out of control in the first place. If you can convince your plants to use up the available nutrients, light, and CO2 faster than the algae does, it'll go away with time.

The Planted Tank forum is nice for additional information on this sort of thing. Most of the information is for tropical tanks, but it applies to cold water as well.

If you can convince your plants to use up the available nutrients, light, and CO2 faster than the algae does, it'll go away with time.

I agree. All of my tanks have gone through a series of different kinds of algae for the first 6 months or so, but once the plants were established or I added water lettuce or hornwort, the algae disappeared. It's virtually non-existent in my tanks. I've also read that Excel kills algae. I use it in my largest tank (started about 6 months ago), and I can recommend it for plants if you want to stay real low tech, and I mean not even DIY CO2. It made a dramatic difference in plant growth.

One downside is that this stuff packs loosely and with burrowing fish it does lead to some plants being uprooted. I didn't have that problem as much in sand at least :/ Here's a piece of grass floating that the surface:

Any guess at ID on that? Obviously it's upside down. It was collected in very shallow water in full sun on the edge of a permanent swamp near Charleston SC.

Here's a commercial plant, still with some adherent potting material, uprooted by the eel:


The front glass is requiring cleaning about every 3 days to maintain visibility. I'm not trying to eradicate algae from the tank; usually I prefer to manage it with a large snail population, but my pond snails have been completely extirpated. Going to have to look for some one of these days. Large ramshorns have survived, but all young are gone and I see no evidence of eggs hatching.

It's been a while since this topic was posted. Do you have any updated photos of what the tank looks like now?