View Full Version : 120 gallon tank question

11-22-2006, 09:48 PM
My dad doesn't take care of his tank and he asked me to help...he has an undergravel filter for the past like 6 yrs that he never does anything with... how do i upkeep it?? is it even worth to keep it for him or should i get something that would be more easier for him... his ammonia is jacked way high and now that i noticed this i have been doing 25 % water changes every week to try to bring it down we have been using ammo lock but i was just wondering if the filter undergravel thing has something to do with this high ammonia.. he just installed a cascade 1200 but i was wondering if this cascade would be enough to filter the tank by itself or should we keep the undergravel filter too?? thanks!

11-22-2006, 10:03 PM
You should be doing massive 70% waterchanges if your detecting amonia! Amonia can kill fish quickly!

The Cascade 1200 will help a lot once established, but is only barely adequate. I am not a fan of the cascade design, but they can provide decent service.

Personally I am against Undergravel filters, they are GREAT for a while 1-2 years, and then they become toxic nightmares. A good old sponge filter like a Lustar Hydro V with a small powerhead is equal to 85-90% of the capacity and a whole lot easier to service.

If your not using a Python (or similar) for your water changes get one... you'll be glad you did ten times over.

11-26-2006, 10:43 AM
Yeah, I'd pull that undergravel filter out in a heartbeat. Get a couple fairly large canisters or one canister and a HOB bio wheel. Like rusty said, do 50-75 percent water changes and you'll see a big improvement.

12-01-2006, 03:18 PM
For the moment, try siphoning directly from the uplift tubes. If there is a significant amount of debris beneath it, it should pull it out. In addition, the gravel needs to be vacuumed thoroughly. The big water changes are the key, as mentioned above.

12-01-2006, 06:15 PM
More than likely if there is detectable ammonia the gravel is clogged up pretty good. Vacuum the substrate in 3 steps, 1/3 at a time with 2 days between sections. I would slap on at least one filter in preparation for removing the ugf plate. I would strongly consider a cannister as it can go a good month with out servicing, there by reducing what you absolutely need to do in order to get the tank in the right direction.

The idea of siphoning from the uplifting tubes is a very good idea. I would siphon 1/3 of the gravel with a 25% volume change. Then I would suck from the uplift tube until it runs clear or an additional 50% volume is removed. Then fill back up. The next day I would check the ammonia levels, if they are still insane then another 50% change via the uplift tubes.
I would repeat this until the substrate has been cleaned. If you remove too much ammonia the tank will not cycle which is the eventual goal.