I think i have crashed my tank
yesterday my ammonia,nitrite were 0ppm and nitrates were 5ppm ph always
8. But my tank had a lot of algae (brown and green) and the filter was very mucky
so i cleaned the algae off and rinsed out the filter,swished the sponges and carbon in tank water ,I tested my water tonite ammonia was 4 or 8 not sure very dark green nitrites were 2ppm and nitrates about 80
I have done a 50% water change and retested
ammonia 2ppm nitrites less than0.25 nitrates down to 20 but the ph is 7.8 as i did not have time to let it stand for a while it is 7.4 when it comes out of the tap i add dechlorinator let it stand for 24 hours and it goes up to 8
Help please i do not know what to do i will have to wait 24 hours now before i can do another water change can she survive those levels?

Sorry to hear of your probs.

I would guess your water has dissolved carbon dioxide to buffer it down (very common). I'd prepare water a day in advance before changing half the tank water to let the carbon dioxide escape.

Just keep up with your daily water changes and fingers crossed.

Slugger

Thank you Slugger For your reply
I panicked When i saw the ammonia results as i am so used to the results being the same i began to wonder if my test kit was faulty,
i have been doing water changes every day and yesterday i had it all down:ammonia was 0.50 nitrites 0.50 nitrates 10.
About the ph i wondered why it was 7.4 at the tap and overnight it would go up to 8, i used an airstone in the bucket, sometimes i left it out to see if it made a difference but always it would be 8 in the morning i even thought it might be the dechlorinator
anyway thank you for your help