ugf

Question
hi there, ihave 30 gallon tank with live rock , 2 powerheads, and the penguin filter with the rotating cartridge at the top of the tank...
my uunderground filter about every 4months gets clogged i think and stops working.. it seems when i buy a new airpump it works again for another 3months.. do i really have to have any airpump/ugf.??? is it really necessary.. i do water changes every 3 weeks and i do 80 percent. i watch my salinity, ph, etc often... thank you also i have a seahorse, a bubble anenome, two tangs, and flame angel and clown

Answer
Hi Tam. Under gravel filters are notorious for having problems with clogging, especially when you are using them with a finer sand like the ones you commonly use in a saltwater tank. Unfortunately the only options you may have here is to either to replace the airpump with two powerheads of equal gph, or get rid of the under gravel filter plate from your tank. If no air is supplied to the undergravel filter it causes an oxygen poor environment where some anaerobic bacteria can colonize and cause an area of trapped sulfuric gases to accumulate. These gases when released into the water column can cause a toxic tank syndrome and basically kill off all the inhabitants in your tank. A very serious condition if not properly taken car of. Removing the filter plate will ensure that this does not happen. An under gravel filter is not a necessary piece of equipment but since you do have one in place it will cause a few problems in removing it. First of all there is usually a lot of debris that accumulates under the plates and removing them will stir this up and can cause your tank to be cloudy for days. You also run the risk of losing a great deal of biological filtration when you remove this kind of filter. So much so that your tank may go through a new cycling period after it is removed and ammonia may reach high enough levels to be toxic to your fish. The problem may not be with the under gravel filter but more with the air pumps you are buying. All air pumps will lose efficiency over time. If you are getting a pump that is rated for your size tank or smaller you may want to upgrade to a much larger model. Another way to keep your under gravel filter working efficiently is to use powerheads on the uplift tubes rather than an airpump. With an airpump the air is forced down the tubes and create a suction of water that flows from under the filter plate. A powerhead will forego the air/suction and simply just suck the water from under the plate. The whole concept of the under gravel filter is to create an area of well oxygenated, flowing, water where your good bacteria can colonize. A powerhead will actually work much better in performing this function than an airpump.