Freshwater Aquarium/ammonia


QUESTION: I have had my 45g high tank setup for about 2 years running great. Mind you had a lot of fish but started with 2 filters 1) Aquaclear 70 and a 2) Fuval 206. Only problem was a little algae caused because I kept leaving light on. Started with 7 Chilids and a small placo and small cat, after about 10 months addeds two Oscars, red and a tiger, still all good (although knew sooner or later would have to get rid of some) until 3 weeks ago ammonia spiked bad off the chart, everything else stayed "0" I took the following remedies to date and still stuck

(Level off chart)
day 1 WC 4gall
" 3 WC 3 g
" 6 WC 15 g and vacuumed very well bottom
" 10 WC 15 g changed carbon on filter and add tetra Safe start Bottle
" 14 WC 10 g changed carbon other and added ammo chips removed 3
fish (2 chilids, 2.5 inch and 3.5 and red Oscar4.5 )
( level 2ppm)
" 20 WC 8 added filstar xp M fiter more fresh ammo in new filter and
slowly added bottle 100ml of Am Guard (Seachem) over
35 hr period no change
STILL 2 PPM although water is Crystal Clear totaly

Now What!! everything else stayed perfect


The first thing you're going to have to do is decide which fish you want to either get rid of, or get a new tank for. Cichlids, especially Oscars are very messy and your tank is overcrowded. A 45 gallon is NOT big enough for 2 adult Oscars by themselves, let alone with the others you have with them. So you'll have to make that decision.

The ONLY way to control ammonia is with water changes. Tetra Safe Start, ammo chips and any other chemicals you can add simply don't work. They may neutralize a little, but for the most part are ineffective.

Decide which fish to rehome, then keep doing 15% water changes every 2 days until your ammonia is at or near 0. Also replace the carbon every week until your ammonia is at or near 0.

Hope this helps, good luck!


---------- FOLLOW-UP ----------

QUESTION: ok got it at present only have about 21.5 iches of fish in tank before i removed some was about 30 which if they told mew correctly should be fine untill the fish get bigger in my 45 high?

But the also told me the more filtration the more fish the tank could handle if you dont make other mistake like not doing water changes etc. is this true or is only the size of the tank

i am now at  
70 gall
45 gall
75 gall
total 190


I don't know what moron told you the more filtration you have, the more fish your tank can handle but that is absolutely NOT true. I'm sorry that you were given such bad information. The rule is 1" of adult fish per gallon of water. So don't go get nine 5" fish and think they will be ok in a 45 gallon because these nine 5" fish will be nine 12" fish in a few months.

The 1" of fish rule is not only for ammonia and other toxins, but you also have to give fish room to grow and swim. Cichlids, especially Oscars, need a lot of swimming room.

Hope this helps, good luck!


---------- FOLLOW-UP ----------

QUESTION: OK got thank you for your honesty But why than now with only 21.5 inches of fish ( i realize that when they grow up I will have to either get bigger tank or remove some from this one)  but only 21.5 inches why am i still having problems now!!
Had 30 inches when started removed 9 18 days ago and still wont drop bellow 2ppm been changing water about 2 5 gallon buckets filled to about 4 gallons each total 8 (w/ prime} now every 2 days since you told me to plus before. I was never over limit before and not now why wont it reduce i am worried that w/ long term contact with the ammonia the fish going to have problems all else remains good except pH is there anything else that could have caused this or keeping me from returning to normal numbers. Also just to let you know there is an air bubbler in tank which i assume cant hurt? and should I remove any of the filters the last one is big enough to handle 75 gallon canister the other is 70 gallons on top and last is canister supposed to max out at 45  although i do like the cannisters the best (Despite all though water is absolutely crystal clear

You'll have to keep doing water changes, 15% every couple of days until the numbers are in the safe zone. Also make sure you siphon the gravel, excess food and waste in the gravel will cause an ammonia spike. Make sure there are no dead fish in the tank behind decor, this also causes an ammonia spike.

The air bubbler is good and no do not remove any of the filters. Just make sure you are properly maintaining your filters (replacing the carbon and cleaning the intake and return) Check the flow rate of the filter, make sure there is nothing blocking the flow and the hoses are tight and secure.

Hope this helps, good luck!


Freshwater Aquarium

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Richard Hight


I own and maintain several freshwater aquariums from 2 to 180 gallon. I can answer most questions about freshwater aquariums, including setup, cycling, maintenance, compatible tank mates, feeding. Moving? I've moved fish both across town and across the country and can help you get your little aquatic friends to their new home safely. I know and have experience with most freshwater community fish, South American Cichlids and African Cichlids. I don't answer questions about Goldfish or keeping Goldfish with Tropical Fish. I also don't answer questions about keeping crustaceans (shrimp, snails, crabs etc) with Tropical Fish, nor questions about saltwater fish or aquariums. I'm not available to answer questions on weekends, this is when I do maintenance on my own tanks.


Many years of personal experience with community tank fish, semi-aggressive fish (Barbs, Tetras, etc), Angels, South American Cichlids and African Cichlids.

HSG 2010-2011 prof

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