Cichlids flashing/rubbing on sand and rocks

[ShaunRowley]

I just started up a cichlid tank and About a week and a half/two weeks ago I did a massive filter clean, cleaned the tubes, intake, exhaust, impeller, filter pads. I cleaned just about everything except the filter media such as carbon and lava rocks which I use as biological filtration (because I'm poor). My ammonia reads .25 ppm and my nitrite 0 ppm. I put bacteria supplement in right around the time the problem arose which was maybe a week and a day or so because I knew I wiped out tons of bacteria. I also bought plastic bio balls to replace my lava rock bio filtration because I figured it was about time.
My question is, is this a direct result of the filter cleaning? Or could it be something else?
I should also mention I'm quite new to cichlids so any tips would be a great help. Thanks

 

[Wolfsblood]

They will do it when something in the water is irritating them i.e. high ammonia, nitrite, or nitrates.

 

[ShaunRowley]

I knew that but how do i lower the ammonia, nitrite, nitrates? I've been doing a water changes very frequently, added media for bio filtration and added bacteria supplement to kick start the bio filtration. My cichlids appear VERY agitated and I'm getting worried because they are flashing more frequently and violently

 

[Wolfsblood]

Was this a cycled tank that was already established before you decided to do cichlids? If it was a brand new tank this link will be helpful Fish-in Cycling: Step over into the dark side - Aquarium Advice

 

[ShaunRowley]

No it's been established for about 6 months already. But I just recently decided to do away with my old fish and gravel and do a cichlid tank with sand

 

[Wolfsblood]

Yea if you changed everything including the substrate it's going to be like a brand new tank. Best you can do now is frequent large water changes when the parameters get a bit off. Hopefully you didn't fully stock it.