Is Coral Gravel Okey For Plants?

[happyadd]

Hi All;

I have recently switched back from keeping malawi's to regular tropical freshwater. However, to save the cost of putting new gravel or sand in my 4ft tank I left the coral gravel there, plus this would help "seed" the new setup. I buffered the water down originally and added a few fish, which are doing perfectly. After a few water changes and the ph stabalised to 7, I went out and bought a load of plants.

I picked up a CO2 diffuser and planted the tank up, we're talking 75ish plants. The co2 is diffusing nicely and I top it up every day. However, having had the tank planted for a fortnight, the plants aren't really taking, I'm losing a few. I'm also feeding the plants daily. The plants are not potted, held down with lead or bunched using cotton wool. I have simply made a hole in the gravel with my finger, put the cuttings or rooted parts in and covered them.

Any advise as to why this may be, or shall I give it a while for the CO2 to kick in. lights are on for approx 12 hours a day and I have no air pump running while the lights are on.

Could it be the coral gravel?

Any responses would be much appreciated.

Thanks Guys!

Adam

 

[Colin_T]

It’s probably the coral rubble. It might be too course for the roots or it could be too alkaline for the plants. Most plants don't like really alkaline water and having their new roots trying to grow into a calcium carbonate substrate would probably upset them.

I'm a bit surprised your PH didn't go back up after you lowered it. Normally if you have coral rubble or shells in the tank they push the PH back up after a few hours. Have you checked your PH test kit?

It might also be your choice of plants. Are they true aquatics, or marsh plants?

 

[Themuleous]

I wouldn't use it, it'll increase the GH of the water.

Sam