Cichlids by Sanderling

The Fluval G Series Hydrotech is here…

// November 19th, 2009 // 8 Comments » // Equipment Reviews, Filtration, Fluval G Series Canister Filter

The latest ‘must have’ addition to the fish room is the new Fluval G- Series  filter. We recently aquired a new G-6 model for an independant technical review  in our fish room.

This compact little unit is rated for superior filtration performance on a 160 gallon (600 L) at a flow rate of  265 gph (1000 L/hr). It offers the traditional mechanical and biological filtration that all fishkeepers know and love, in addition to chemical filtration, with the ability to remove nuisance compounds like nitrates and phosphates. Of particular interest is an onboard processor and sensor array that measures conductivity and temperature of the system water, storing up to 48 days worth of historical data for trending purposes. The liquid crystal display also includes counters to advise when it is time to perform maintenance on the chemical, mechanical or biological filter media.

Fluval claims that the bio-media requires maintenance at six month intervals and packages it deep inside the highly compact, low power consumption enclosure. The chemical and mechanical filter media is easily removed from access wells located on the top of the unit, eliminating the need to dismantle the filter and disrupt the bio-media. All in all the G Series looks impressive and  recently there has been a lot marketing hype on the internet and the trade show circuit. Fluval has been ‘talking the the talk ‘as the next  generation in aquarium filter technology- but does it ‘walk the walk?’

Over the next couple of days Sanderling will be putting this product through it’s paces, first with a documentation and set up review and then in the days and weeks that follow, we’ll measure performance, maintainability and post comments from other users. Make sure you check back on a regular basis as we drive what looks like a thoroughbred filter around the performance track !

(more…)

Removing Surface Films From Fish Tanks

// November 1st, 2009 // No Comments » // Filtration, Fish Room Projects

12 hour acumulation of surface film

One of the benefits of having powerful bio-filtration system, is having the option of increasing loading densities and increasing feed rates without risk of high ammonia or nitrite levels as a result. The down side of doing this however is the accumulation of a thin film of lipo-protein and fish oils from that does not get digested by the biofilter because, being lighter than water it is unable to get to the sump. The image above shows the accumulation after 12 hours.

Its considered good practice to remove water from the bottom  of a tank as this tends to be the area of lowest oxygen concentration. The original drain design includes a spool piece that extends to the bottom of the tank and a strainer to keep young fish out of the sump. By adding a horizontal perforated piece and extending the strainer out to the center of the tank, the drain assembly also acts as a surface strainer. Below is an image of the new assembly;

New drain assembly

 A mesh bag keeps smaller fish from a roller coaster ride to the sump and the return pump impellor;

Here is some video of a trial using a prototype. The extension of the horizontal piece towarrds the center of the tank effectively divides the surface of the tank in two. The film is pushed into a gyre that rotates across the front edge of the skimmer and is gradually reduced. See the videos below;

Lids were recently placed on the tanks now that the cooler weather is here in order to reduce heat and moisture loss. This has the disadvantage of reducing the amount of oxygen that can diffuse into the water at the surface. To compensate, sponge filters were added to provide some makeup air above the surface of the tank and ensure that sufficient oxygen levels a e maintained. By careful placement at the center of the gyre, the film is pushed to the outside and and against the skimmer, facilitating its constant and rapid removal;

Rena’s XP Series Filters and Snails

// October 23rd, 2009 // No Comments » // Filtration

Nitrosonomas and Nitrobacter both produce thin sticky films as they grow and divide on biomedia. These films grab organic fines from the water passing by which feed competing heterotrophic bacteria. Over time, unless actively grazed by detritovores like snails, these films become thick enough and organic rich enough that heterotrophic bacteria colonize them, and begin feeding on the trapped organic fines as well as the film itself. Because the hetertroph population can grow so much faster than the two N’s they eventually outcompete and destroy the colony by consumming most of the available oxygen.

If this happens in your filter it will be evident in milky, stringy discharges (rotting film) at start up after cleaning or if you have unplugged the filter for some other reason. Stringy discharges may be seen periodically while running as well. Generally its nothing to be overly concerned about since the heterotrophs will eventually die off and the media will be again becolonized by the two N’s.

What it indicates is that the media is not optimized for nitrification and your system would benefit from a mechanical prefilter to reduce the amount of suspended organic material channeling through the filter and fouling the thin film created by the two N’s. You can use fine pore filter media but this will tend to clog up and reduce the flow rate through the  filter which can cause other problems, including oxygen depletion and general lack of performance. Alternatively you can use snails to clean the bacteria film!

When using canister filters I prefer the Rena Filstar series due to the quiet and powerful pump and the roomy media baskets. I fill them up with Fluval Prefilter media which is open enough to allow small snails complete access to maintain the bacterial film by actively grazing upon it. The impellor crushes a few up ocaisionally and sends them back to tank as fresh food for the fish.

When I clean these filters out annually, I always make sure to toss a few adult snails back into the filter before putting the lid on. I don’t run with the filter pads, but still have low turbidity in my tanks.

The ability to house snails for this synergistic biofiltration aproach is what sets the XP series of filters apart from the rest of the cannister herd in my humble opinion.

Turning Sump Design on It’s Head

// October 10th, 2009 // No Comments » // Filtration, Fish Room Projects

I’ve always been a cannister and HOB filtration kind of guy. I also like sponge filters but in spite of more than twenty active years in the hobby I’ve never had a sump. I guess I’d rather use any container big enough to be a sump to keep fish!

All good ideas have their moment however and it was simply a matter of time until I needed the bio-filtration power that only a sump with wet/dry flow capability can offer.

I recently put together a fry growing module for three species of Aulonocara in my fish room. The setup was simple enough; three 110 gallon stock tanks arranged in series filtered by a Fluval FX-5. Rated at 600 plus, gallons per hour, I figured the filter could handle the bio load no problem. As the population of juveniles and sub adult Peacocks approached 500 or so, I realized that with the amount of food I was using, I needed more filtration power than my original setup could provide.

I found a powerful submersible pump rated at 3000 gph. By running the tanks in parallel rather than in series, and collecting the discharge in a sump through separate drains, I could have ten turns per hour in each tank-plenty of filtration!

My fish room is located in the unfinished corner of the basement of our house, usually known as the furnace room. This is only the real estate that my wife has allowed me, unencumbered, to indulge in my hobby. It has become very crowded and finding room for a traditional sump design big enough for a 330 gallon system would be difficult. In fact I only had an area 2 ft square to work with,  squeezed in between my water heater and my new system.

I decided the only logical approach would be to build a stacked system; a bio-tower above a sump, with a return manifold fed from the 3000 gph submersible pump, located in the sump.

I settled upon a 50 gallon sewage basin as my sump. If your considering using one keep in mind they are pricey but there is lttle chance you’ll be tempted to use it as a fish tank and scrap your sump project. They also have the added advantage of having a 4” hub for a drain and a 3″ threaded opening that can bushed to any size you want. There is also a 2″ schedule 40 pipe clearance hole for the discharge line, a removable bolt down access cover, and a bung hole for heater and pump power cords. All in all it is a very neat package, ideal for the application. I got mine at Home Depot for $145 but you may be able to do better at a plumbing supply house.

For those who like to skip to the end to see how the project turned out, I’ve attached a picture of the (nearly) finished product. 

(more…)