it happens..patience is the key..it took me 2 years to understand what each plant species need to grow right an' i'm talking about 12 years back when atleast I did not have internet access to ask questions in forums so spontaneously! so patience my friend..u'll get there. Worst part about a new tank is - the ammonia spike..with regards to the amount of substrate you have your plant count was really less. give a gap of a few days and start again. One thing that I did notice - your tank has a lot of diatome attack, which in a way has changed your water colour as well. IMO - when starting a new setup this is what I follow - 1) 50% WC everyday for 1st 2 weeks 2) 50% WC alternate days for next 2 weeks 3) 50% WC every 3 days for 2 weeks then finally bring it down to 1 - 40% WC weekly. This helps in keeping the tank a lot stabilized. I also follow a lihgt schedule of 4 hrs for first week, and then gradually increase it to 8 over a span of 4 weeks by that time plants stabilize. Reason of doing - most plants we buy are grown emersed so it takes time for them to convert to it's submerged state. During this time it's expected that there would be melt out's but your WC schedule along with controlled lighting helps them not go into a shock and stabilize faster. Now onto ferts - I dose exactly half calculated dosage of my tank(I follow EI using stock solution) for first 4 weeks (reason - plants are already sufering to convert them selves, why stress them out more with ferts to photosynthesise faster that too when it's not required). Last but not the least as I mentioned before - HOB's are not exactly ment for planted tanks so my advice get a canister filter with a 10X filtration rate, if that's too expensive then go for a lower rate but definitely get a power head to increase flow as otherwise algal growth due to low flow is un-avoidable. Now I shared the whole process of how I run my tanks and these steps never dissapointed me till date - hope you give this a shot..my guess it will be a grand success at your end as well.
Good judgement comes from experience, and experience comes from bad judgement.
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