Need help with Lake Malawi Cichlids

[jjacks1]

I'm panicking a little bit.
I have a 20 gallon long aquarium that has 1 dozen Lake Malawi Cichlids. The fish are 1/2" to 3/4". All came out of the same tank at the store and have been in an established aquarium for 1 month. Tank substrate is crushed coral. Undergravel filter with 2 power heads + one bio-wheel filter rated for 50 gallon tank. PH has been a consistant 8.0. No ammonia, no nitrite, no nitrate.
PH has dropped today (to 7.8) and fish are acting odd. (I think) My husband says the fish are acting normally and that I worry too much. Is it normal for cichlids to lie down on their sides and rest? KH is also low, in the 100 - 200 ppm range.
The only things in the tank are rock (lava rock and petrified wood from Kentucky) and one piece of aquarium wood. Plenty of hiding places for the fish.
Have been feeding the fish cichlid flake, cichlid pellets and frozen spirulina shrimp.
Have tried using some PH Up junk but does not seem to be helping.
Filters and water changed last weekend.
Am I worrying about nothing?
And how do I get the PH back up to 8.0 and keep it there? I thought the coral was supposed to take care of that.
Help and thank you.

[KittyKat]

I'm panicking a little bit.

Hi and welcome to the forum, we'll try to help you..

I have a 20 gallon long aquarium that has 1 dozen Lake Malawi Cichlids. The fish are 1/2" to 3/4".

Sounds fine for the moment.. what species are they?

All came out of the same tank at the store and have been in an established aquarium for 1 month.

That is very fast stocking, how did you make sure that it was cycled before adding the fish and at what rate did you add them?

Tank substrate is crushed coral. Undergravel filter with 2 power heads + one bio-wheel filter rated for 50 gallon tank.

Sounds ok.. crushed coral may cause irritation in gills, but that doesn't seem to be your problem here. Do you hoover the gravel to clear it out so that the UG filter works well?

PH has been a consistant 8.0. No ammonia, no nitrite, no nitrate.

How do you get rid of your nitrates? I have never seen a tank with a reading of 0.

PH has dropped today (to 7.8) and fish are acting odd. (I think) My husband says the fish are acting normally and that I worry too much. Is it normal for cichlids to lie down on their sides and rest? KH is also low, in the 100 - 200 ppm range.

Have you done anything to the tank? Water changes, any maintenance (what is your usual maintenance?), added anything new in the last few weeks? You are right, there is something very wrong if African cichlids are down on their sides.

The only things in the tank are rock (lava rock and petrified wood from Kentucky) and one piece of aquarium wood. Plenty of hiding places for the fish.
Have been feeding the fish cichlid flake, cichlid pellets and frozen spirulina shrimp.

Ok, sounds fine too.. how much of which and how often?

Have tried using some PH Up junk but does not seem to be helping.

Junk is the right word, it is not a long term solution.

Filters and water changed last weekend.
Am I worrying about nothing?
And how do I get the PH back up to 8.0 and keep it there? I thought the coral was supposed to take care of that.
Help and thank you.

I think you do have something to worry about! Taking out the wood might help as wood contains tannins which make water more acidic.. is yours a clear colour or that of dilute tea? Is the water clear or cloudy?

[sharkdude]

Was this tank set up before? Your ammonia, nitrite and nitrate readings are exeptional for such a new tank.

Generally no, cichlids do not 'sit' and rest, rift lake cichlids especially. Are there are other things that are different, say only some showing this behaviour? The 'sitting' fish, so they look smaller/larger than normal. Do they move their gills alot?

The pH issue should be resolved by removing the various bits of wood and a good water change Rocks such as ocean rock is a good decor material for rift lakeers.

Good Luck.