Matrix or De*Nitrate for my 54 gallon goldfish tank

[Maca2406]

Hello.

I have a 54 Gal goldfish tank (2 months old) with 16 fish 4" to 5" as you can see my tank is over stocked. I am not able to change the tank size or move fish at this time so I need to find an efficient way of balancing the aquarium. Water changes are 1 for week 20% (40 L) each, clean my canister filter each 15 days and gravel wash once a month so everything else is fine other than my nitrates.

My Nitrate at first month was 10 ppm, second month was 20 ppm, third month....I don't want to see 30 ppm now. Then with this monthly increment soon will have the nitrates outside of control.

I have a PennPlax Cascade 1000 Canister filter setup from below to up with:1-Basket: Fluval ceramic rings prefilter media/Pennplax Bio-Sponge, 2-Basket: Aquarium Pharmaceuticals Ceramic Rings (1 Litre), 3-Basket: Aquarium Pharmaceuticals Bio-Chem Stars (40 stars)/Pennplax Bio-Floss.

Then my question is: What is the best solution for my aquarium balance, Matrix or De*Nitrate. If Matrix (I prefer for the easiness of my filter and I will replacing some bio-media with Matrix) what quantity. If De*nitrate, what quantity and how and where I install it.

Thank you.

[Tech Support CH]

That is a full aquarium. There are three main solutions for dealing with nitrate: Dilution with water changes, removal by live plants, or consumption by bacteria.

Products such as Purigen will help remove it before it becomes nitrate, so it is beneficial to place some in the filter.

You could add some hardy plants, but keep in mind goldfish love to eat plants.

Bacteria will consume nitrates but you have to provide the proper conditions for those bacteria to live. The nitrate consuming bacteria require low to no oxygen conditions. We recommend a slow flowing (less than 50 gph) canister filter filled with de*nitrate. If you can not provide these conditions you can use Matrix , which is larger pieces than de*nitrate. Some de-nitrifying bacteria will grow on the inside of these larger pieces. This is usually enough to help most tanks out but with an overstocked goldfish tank I doubt that it will be much help.

In your case I would recommend that you increase the water change frequency or percentage. Either change 20% twice a week or change 30% once a week. Also you will want to feed really light. The more food you feed the more nitrate will build and the quicker your fish will grow. If you can set up a de-nitrifying filter it would be very beneficial. Depending on how handy you are you could make one with some PVC and a slow flowing powerhead. I have a power point picture of an example. If you would like for me to send it to you please send me a PM with your email address.

Good luck and hopefully you'll be able to give the fish more room soon.

[Maca2406]

Thank you for their help, I will reduce the population soon and attempt with some plants that can survive the goldfish.

A last question: between de*nitrate and matrix, exists great difference in the capacity to establish anaerobic bacteria ???.

Thank you again.

[Tech Support CH]

You are welcome.

Whether you use de*nitrate or Matrix depends on water flow. If the water flow is above 50 gph than you will not get any anaerobic bacteria with de*nitrate although you will get some with Matrix. For the quickest nitrate reduction I recommend de*nitrate with a flow less than 50 gph.

[fishmerised]

Just wanted to add that goldfish of your size (4-5") really need around 10 gallons of water each or you'll be facing "old tank syndrome" in around 6 months. Goldfish produce a lot of waste, they are big eaters comparible to an oscar of the same size.

I have 35 goldfish in 5 tanks and a 200 gallon tub, the stocking levels vary between 5-15 gallons per fish depending on size. Even with weekly water changes the nitrAtes quickly get out of control. I have had success using Purigen to reduce waste levels and therefore reduce nitrAtes.