Trying a pond filter with fountain and UV sterilizer in 75gal tank

[bekateen]

Growing in the aquarium hobby is a series of trials, successes and failures. Here's my next trial. Picked up this beauty with UV sterilizer tonight. This is going into my greenhouse 75 gallon tank that is chronically green with suspended algae. Let's see how how well it works.

[TwoTankAmin]

The price is certainly a deal.

I would be concerned about the fact that 5 in 1 comes in several sizes. But I cannot find flow rates. With UV what it might kill depends on several factors. The trick is to match those factors to the problem one is looking to solve. The considerations are:

Kill level- i.e. what any given set-up can kill.
UV bulb wattage needed.
Dwell time- how long the water will be in contact with the UV as it passes through the unit.
Turnover rate- how many times will all the water pass through the unit in an hour.
Design of the unit aside from the bulb.

I have a small unit which was purchased to sterilize a new 55 gal. tank so it could receive wild Altums. Learning what I needed to know to be able to get what I required for this and why came from here https://www.americanaquariumproducts.co ... ation.html Mine was a 9w bulb. The unit was external to the tank and was powered by a powerhead in the tank.

If you already know this stuff, then you don't need it. But I figure better to provide it than not.

I am curious how you will prevent the fountain from shooting water out of the tank?

[bekateen]

Hi TTA,

Thanks for the feedback. Here's a link to the manufacturer's page: https://www.penningtonaquagarden.com/pr ... -in-1-300/
Here's the owner's manual: https://www.penningtonaquagarden.com/wp ... 7882_7.pdf

This is the model 300. Flow rate is only 190 gal/hr... Not bad, but doesn't compare to the 800gph pump I have in my 40 gallon breeder.

This setup has only a 5W UV bulb. Compared to your 9-watter, it doesn't sound like mine will do as much. As far a dwell time, I have no idea. I bought it mainly because it was a pump, filter and fountain all in one and it was on sale for about $90 (half price). The UV light was a bonus. Also, the LED night light isn't really a bonus because I'm sure my nocturnal fish won't appreciate that. I may cover up the light over time. Will need to see how bright it is.

This is my first-ever UV system. The owner's manual says I need to replace the bulb once every 6months/season. Is that the lifespan of a UV bulb???

Cheers, Eric

[TwoTankAmin]

eric-

Here is what Carl S. the founder of the site I linked says in his very complete information re UV and changing bulbs.

Bulb: Check your UV Bulb/Lamp every month if possible. More importantly, CHANGE your bulb every 6 months for aquariums (run 24/7 as suggested earlier in this article), and also every 6 months for ponds in warm climates where there is no winter freeze. While many non-professionals will quote manufacturers that one year or 8000-9000 hours is when to change, this error is based on the "rated" lifespan" of the HO UV lamp/bulb. HOWEVER, at 6 months the lamp is already at 75% of its UVC output and at one year it is at 50% of its original UVC output which is why I strongly recommend every six months.

In cool climates a pond UV bulb can be changed every season (usually late spring/ early summer), however as your pond UV Sterilizer approaches a year, your UV-C Lamp is only emitting about 25% of the correct UVC energy, so changing a pond UV bulb once per year say in Sept. will not be of much benefit since it will be very inefficient when you need it most (the warm/hot months of summer).

If you are not getting this unit because you want the UV, you do not need to worry much about it all. It is possible with the proper UV unit to deal with algae, to kill bacteria and even viruses. It can also kill parasites. If this is important to you, then for sure read as much of Carl's information on UV as you can. It is long, it is very detailed and when you have finished reading you will know more about the use of UV and what unit to get and how to calculate it all.

I have not had cause to use it since when I was getting the Altums, but Carl makes some very good arguments for using one on a tank 24/7. However, it would be quite pricey to do so if one has a lot of tanks. Also, I have never had a disease etc. outbreak that did not happen in a Q tank. I did not have the unit back then nor did I know anything at all about UV for tanks.

[Viktor Jarikov]

Great links and info. Thank you. My only experience with the UV was back then when we had a 12,000 gal outdoor koi pond in Rochester, NY in 2006-2011. We needed it to clear up the green water. The bulb was 40W. The pump was nominally 3000 GPH, probably more like 2500 GPH. There were a ton of plants in the pond, including water hyacinths, competing with the green soup for nutrients. The UV kept our water really clear.