My Fish Are Dying!

[vcmtik]

Hi everyone.

I have had this tank since July. Unfortunately I was badly advised by my LFS about cycling my tank beforehand, so I had to do a fish-in cycle. My tank finally cycled in October (with much thanks to FishForums.net!!). Everything has been ticking over nicely, I have slowly introduced more fish with no problems. It has been 8 weeks since I introduced the last fish (4 platys). During the last 2 weeks, I have been losing fish and snails almost daily. I am constantly checking my levels which are:

Ammonia: 0
Nitrite: 0
Nirate: 20

The only readings that are changing is my ph. My tap water is 7.6, but 1 week after a water change the level dips to 6.0 - 6.2 in the aquarium. Could this be the problem? The fish are not showing any ill-effects regarding feeding, physical appearance or behaviour.

My details are:

125 litre tank
Fluval u2 filter
Fluval u3 filter
3 x airstones
sand substrate
1 x sml piece of bogwood (i removed the larger pieces as it can affect ph)
lighting for approx 15hrs a day
Temperature:26.6 c
my stock is:

4 x tiger barbs (5 months)
2 x mollies (5 months)
2 x platys (2 months)
1 x senegal bichir (4 months)
3 x dwarf gouramis (4 months)
3 x silver sharks (3 months about 3" long)
5 x chequered barbs (3 months)
2 x corydoras (10 weeks)
1 x golden apple snail (4 months)

Recently I have lost:

5 x apple snails
1 x gourami
2 x rams
2 x platys

I have various live plants, regularly maintained.

I use Seachem Prime every routine water change. I live in the UK.

Any advice would be appreciated.

Thanks

 

[zwright]

It could be the ph. How quickly is it dropping day to day, I know you said it goes from 7.6 to 6 in a week, which is not great, but if it droping say 7.6-7 in less than 24 hours that could be your problem. You may want to think about adding some crushed coral to your filter to help maintain a stable pH. Crushed coral will help raise your pH, so ideally it won't drop from week to week.

 

[vcmtik]

Will the coral affect my freshwater fish? By the way, my last snail died this morning Looking at records of previous readings, the ph lowers quickly. Day 1 ph was 7.6 on Day 4 it fell to 6.4. So it's dropping at a rate of .4 every 24 hours.

 

[WILDER]

Your tanks severely overstocked.

What the name of the test kit you are using.

Bogwood lowers ph.
Do you have any rocks or ornaments in the tank.

If ph changes dramatically fish can die of ph shock.

Your tank ph should be around the reading of the tap ph.

 

[vcmtik]

The test kits that I use are the API liquid test kits. I have a few resin ornaments and a couple if ornamental rocks. I don't know what kind they are, but I have had them for years, and didn't seem to affect the water in my old aquariums. Hope this helps.

 

[WILDER]

Remove the bogwood.
Start to do some small water changes.
Then keep testing your water in ph to see if it goes back up.

 

[vcmtik]

Okay will do. What % w/c do you recommend?

 

[loraxchick]

do you use CO2? how often do you substrate/filter clean (rotting organics can lower pH). crushed coral is a good idea and will not harm your fish. another idea is clam shells which are very well boiled and scrubbed. smash them up with a hammer and either place them in the filter or sprinkle around the substrate. this will slowly bring pH up over the course of a week or so and help it remain stable.
as mentioned bogwood can lower pH. how long have you had the wood in the tank? did you soak it first to remove the tannins/is it still leeching tannins (if not, i wouldnt worry about the wood as the pH factor).
best of luck, hope it gets sorted for you.
cheers

 

[vcmtik]

Hi

I don't use co2. I clean substrate weekly, and the filters fortnightly on rotation. I have had the bogwood since August, it doesn't leak tannins at all. I have just tested ph it is 6.4, it was 7.4 6 days ago. I was going to change 10% and remove decaying leaves if there any. Will that be okay to start with?

 

[loraxchick]

do you use CO2? how often do you substrate/filter clean (rotting organics can lower pH). crushed coral is a good idea and will not harm your fish. another idea is clam shells which are very well boiled and scrubbed. smash them up with a hammer and either place them in the filter or sprinkle around the substrate. this will slowly bring pH up over the course of a week or so and help it remain stable.
as mentioned bogwood can lower pH. how long have you had the wood in the tank? did you soak it first to remove the tannins/is it still leeching tannins (if not, i wouldnt worry about the wood as the pH factor).

"Recently I have lost:

5 x apple snails
1 x gourami
2 x rams
2 x platys"
if dosing copper or low "hardness" (soft) water (which i am assuming you have as the fluctuation of pH indicates) the snails may have died from either copper exposure (inverts are sensitive to copper) or not having enough calcium for thier shells. aso lack of food if the other tankmates eat it all before they get a chance (they do not eat just algae or plants).
likely the gourami was killed by the other gouramis (they can be territorial)
depending on which ram species, either temp or pH (i think they like alkaline water-could be wrong but im fairly certain)
platys- ?? beat up by tankmates? difficult labor?
1.5 change in pH is pretty good drop, but many folks running co2 see daily fluctuation of 1 on the pH scale, and that is daily-not over the course of a week. just something to think about. i really think you need to "buffer" your water with some sort of carbon source (coral or crushed shells).
best of luck, hope it gets sorted for you.
cheers
*edit to add*

 

[vcmtik]

Okay. I shall get on and by crushed coral asap.

Thanks

 

[furry catfish]

Your tanks severely overstocked

wilder is right,If google is right then you have a 27 gallon tank which is in no way a suitable enviroment for a senegal bichir,they are just about ok in a 40 gallon ,I would get rid of it.Also silver sharks need,If I remeber correctly,is a 55 gallon minimum I think bigger.and the tiger barbs are active and need a large shoal so a 27 gallon is to small.Every thing else is fine,but rehouse the other fish,your filteration is good so you can have a few more fish after you stabilise the ph and cycle,I think


good luck



chris